Post on the topic of beneficial bacteria. What bacteria make up the intestinal flora? Beneficial bacteria that live in the gut

Most people associate the word "bacteria" with something unpleasant and a threat to health. At best, remembered dairy products... At worst - dysbiosis, plague, dysentery and other troubles. And bacteria are everywhere, they are good and bad. What can microorganisms hide?

What are bacteria

Bacteria translated from Greek means "stick". This name does not imply that harmful bacteria are meant. This name was given to them because of the shape. Most of these single cells look like rods. They also come in the form of triangles, squares, star cells. For a billion years, bacteria do not change their appearance, they can only change internally. They can be mobile or motionless. A bacterium is made up of one cell. Outside, it is covered with a thin shell. This allows her to keep her shape. There is no nucleus or chlorophyll inside the cell. There are ribosomes, vacuoles, outgrowths of the cytoplasm, protoplasm. The largest bacteria was found in 1999. It was named "The Gray Pearl of Namibia". Bacteria and bacillus mean the same thing, only they have different origins.

Man and bacteria

In our body, there is a constant struggle, which is waged by harmful and beneficial bacteria. Through this process, a person receives protection from various infections. Various microorganisms surround us at every turn. They live on clothes, they fly in the air, they are omnipresent.

The presence of bacteria in the mouth, and this is about forty thousand microorganisms, protects the gums from bleeding, from periodontal disease and even from sore throat. If a woman's microflora is disturbed, she may begin gynecological diseases... Observance of basic rules of personal hygiene will help to avoid such failures.

Human immunity completely depends on the state of microflora. The gastrointestinal tract alone contains almost 60% of all bacteria. The rest settled in respiratory system and in the genital area. A person lives about two kilograms of bacteria.

The appearance of bacteria in the body

A newly born baby has a sterile intestine.
After his first breath, many microorganisms enter the body, with which he was not previously familiar. When the baby is first applied to the breast, the mother transfers beneficial bacteria with milk, which will help normalize the intestinal microflora. It is not for nothing that doctors insist that the mother, immediately after the birth of her child, breastfeed him. They also recommend extending this feed as long as possible.

Beneficial bacteria

Beneficial bacteria there are: lactic acid, bifidobacteria, Escherichia coli, streptomycents, mycorrhiza, cyanobacteria.

They all play an important role in human life. Some of them prevent the appearance of infections, others are used in production drugs, the third maintain balance in the ecosystem of our planet.

Types of harmful bacteria

Harmful bacteria can cause a number of serious diseases in humans. For example, diphtheria, anthrax, sore throat, plague and many others. They are easily transmitted from an infected person through air, food, and touch. It is the harmful bacteria, the names of which will be given below, that spoil food. They give off an unpleasant odor, putrefaction and decomposition, they cause disease.

Bacteria can be gram-positive, gram-negative, rod-shaped.

Names of harmful bacteria

Table. Harmful bacteria to humans. Names

Names	Habitat	Harm
Mycobacteria	food, water	tuberculosis, leprosy, ulcer
Tetanus stick	soil, skin, digestive tract	tetanus, muscle cramps, respiratory distress
Plague wand (considered by experts as a biological weapon)	only in humans, rodents and mammals	bubonic plague, pneumonia, skin infections
Helicobacter pylori	human stomach mucosa	gastritis, peptic ulcer, produces cytoxins, ammonia
Anti-ulcer stick	the soil	anthrax
Botulism stick	food, contaminated dishes	poisoning

Harmful bacteria are able to stay in the body for a long time and absorb useful substances from it. However, they are capable of causing an infectious disease.

The most dangerous bacteria

One of the most resistant bacteria is methicillin. It is better known as Staphylococcus aureus (Staphylococcus aureus). This microorganism is capable of causing not one but several infectious diseases. Some of these bacteria are resistant to powerful antibiotics and antiseptics. Strains of this bacterium can live in the upper respiratory tract, in open wounds and in the urinary tract of every third inhabitant of the Earth. For a person with strong immunity it is not dangerous.

Harmful bacteria to humans are also pathogens called Salmonella typhi. They are pathogens acute infection intestines and typhoid fever. These types of bacteria, harmful to humans, are dangerous in that they produce toxic substances that are extremely life-threatening. With the course of the disease, intoxication of the body occurs, a very strong fever, rashes on the body, the liver and spleen increase. The bacterium is very resistant to various external influences. Lives well in water, vegetables, fruits and reproduces well in milk products.

Clostridium tetan bacterium is also among the most dangerous bacteria. She produces a poison called tetanus exotoxin. People who become infected with this pathogen experience terrible pain, seizures and die very hard. The disease is called tetanus. Despite the fact that the vaccine was created back in 1890, 60 thousand people die from it every year.

And another bacterium that can lead to human death is Mycobacterium tuberculosis. It causes tuberculosis, which is resistant to drugs. If you do not seek help in a timely manner, a person may die.

Measures to prevent the spread of infections

Harmful bacteria, the names of microorganisms are studied from the student's bench by doctors of all directions. Every year, health care is looking for new methods to prevent the spread of infections that are life-threatening. With the observance of preventive measures, you will not have to waste energy looking for new ways to combat such diseases.

To do this, it is necessary to identify the source of the infection in time, to determine the circle of sick and possible victims. It is imperative to isolate those who are infected and disinfect the focus of infection.

The second step is to destroy the pathways through which harmful bacteria can be transmitted. To do this, conduct appropriate propaganda among the population.

Food objects, reservoirs, warehouses with food storage are taken under control.

Each person can resist harmful bacteria, strengthening their immunity in every possible way. Healthy way life, adherence to basic hygiene rules, protecting oneself during sexual intercourse, the use of sterile disposable medical instruments and equipment, a complete restriction from communicating with people in quarantine. When entering the epidemiological area or the focus of infection, it is necessary to strictly comply with all the requirements of the sanitary and epidemiological services. A number of infections are equated in their effect with bacteriological weapons.

Bacteria are good and bad. Bacteria in human life

Bacteria are the most numerous inhabitants of the planet Earth. They settled it in ancient times and continue to exist to this day. Some species have even changed little since then. Bacteria useful and harmful literally surround us everywhere (and even penetrate into other organisms). With a rather primitive unicellular structure, they are probably one of the most effective forms of living nature and stand out in a special kingdom.

Margin of safety

These microorganisms, as they say, do not drown in water and do not burn in fire. Literally: they can withstand temperatures up to plus 90 degrees, freezing, lack of oxygen, pressure - high and low. We can say that nature has put in them a huge margin of safety.

Bacteria beneficial and harmful to the human body

As a rule, the bacteria that inhabit our bodies in abundance are not given the attention they deserve. After all, they are so small that they seem to have no significant meaning. Those who think so are largely mistaken. Bacteria useful and harmful have long and reliably "colonized" other organisms, successfully coexist with them. Yes, they cannot be seen without the help of optics, but they can benefit or harm our body.

Who lives in the intestines?

Doctors say that if you put together just the bacteria that live in the intestines, and weigh it, you get something about three kilograms! One cannot but reckon with such a huge army. Many of the microorganisms continuously entered the human intestine, but only some species find favorable conditions for living and living there. And in the process of evolution, they even formed a permanent microflora, which is designed to perform important physiological functions.

"Wise" neighbors

Bacteria have long played an important role in human life, although until very recently people had no idea about it. They aid their host with digestion and a number of other functions. What are these invisible neighbors?

Permanent microflora

99% of the population resides permanently in the intestines. They are ardent adherents and helpers of man.

• Essential beneficial bacteria. Names: bifidobacteria and bacteroids. The overwhelming majority of them.
• Associated beneficial bacteria. Names: Escherichia coli, enterococci, lactobacilli. Their number should be 1-9% of the total.

It is also necessary to know that under appropriate negative conditions, all these representatives of the intestinal flora (with the exception of bifidobacteria) can cause diseases.

What are they doing?

The main function of these bacteria is to help us with the digestion process. It has been noticed that a person with improper nutrition can develop dysbiosis. As a result, stagnation and feeling unwell, constipation and other inconveniences. With the normalization of the nutritional balance, the disease, as a rule, recedes.

Another function of these bacteria is guarding. They keep track of what bacteria are good for. To ensure that "outsiders" do not penetrate their community. If, for example, the causative agent of dysentery, Shigella Sonne, tries to enter the intestines, they kill her. However, it is worth noting that this happens only in the body relatively healthy person, with good immunity. Otherwise, the risk of getting sick increases significantly.

Unstable microflora

Approximately 1% in the body of a healthy individual are so-called opportunistic microbes. They belong to the unstable microflora. Under normal conditions, they perform certain functions that do not harm a person, they work for the good. But in a certain situation, they can manifest themselves as pests. These are mainly staphylococci and various kinds of fungi.

Dislocation in the gastrointestinal tract

Actually, the entire digestive tract has a heterogeneous and unstable microflora - bacteria are good and bad. The esophagus contains the same inhabitants as in the oral cavity. In the stomach there are only a few that are resistant to acid: lactobacilli, helicobacters, streptococci, mushrooms. V small intestine microflora is also scarce. Most bacteria are found in the colon. So, defecating, a person is able to excrete over 15 trillion microorganisms per day!

The role of bacteria in nature

It is also certainly great. There are several global functions, without which all life on the planet would probably have ceased to exist long ago. The most important is sanitary. Bacteria eat dead organisms found in nature. They, in essence, work as a kind of wipers, not allowing the accumulation of dead cell deposits. Scientifically they are called saprotrophs.

Another important role of bacteria is participation in the world circulation of substances on land and at sea. On planet Earth, all substances in the biosphere are transferred from one organism to another. Without some bacteria, this transition would simply not have been possible. The role of bacteria is invaluable, for example, in the circulation and reproduction of such an important element as nitrogen. There are certain bacteria in the soil that make nitrogenous fertilizers for plants from nitrogen in the air (microorganisms live right in their roots). This symbiosis between plants and bacteria is being studied by science.

Participation in food chains

As already mentioned, bacteria are the most numerous inhabitants of the biosphere. And accordingly, they can and should participate in the food chains inherent in the nature of animals and plants. Of course, for a person, for example, bacteria are not the main part of the diet (unless they can be used as a food additive). However, there are organisms that feed on bacteria. These organisms, in turn, feed on other animals.

Cyanobacteria

These blue-green algae (an outdated name for these bacteria, fundamentally incorrect from a scientific point of view) are capable of producing a huge amount of oxygen as a result of photosynthesis. Once upon a time, it was they who began to saturate our atmosphere with oxygen. Cyanobacteria continue to successfully do this to this day, forming a certain part of oxygen in the modern atmosphere!

What are bacteria: names and types

The most ancient living organism on our planet. Its representatives not only survived for billions of years, but also possess sufficient strength to destroy all other species on Earth. In this article, we will look at what bacteria are.

Let's talk about their structure, functions, and also name some useful and harmful species.

Discovery of bacteria

Let's start our tour of the microbial kingdom with a definition. What does bacteria mean?

The term comes from the ancient Greek word for "stick". It was introduced into the academic lexicon by Christian Ehrenberg. These are non-nuclear microorganisms, consisting of one cell and without a nucleus. Previously, they were also called "prokaryotes" (non-nuclear). But in 1970 there was a division into archaea and eubacteria. However, until now, this concept is often understood to mean all prokaryotes.

The science of bacteriology studies what bacteria are. Scientists say that at this time about ten thousand different types of these living creatures have been discovered. However, it is believed that there are more than a million varieties.

Anton Leeuwenhoek, Dutch naturalist, microbiologist and Fellow of the Royal Society of London, in 1676, in a letter to Great Britain, describes a number of the simplest microorganisms that he discovered. His message shocked the public, a commission was sent from London in order to double-check this data.

After Nehemiah Gru confirmed the information, Leeuwenhoek became a world-famous scientist, the discoverer of the simplest organisms. But in his notes, he called them "animalculi".

His work was continued by Ehrenberg. It was this researcher who coined the modern term "bacteria" in 1828.

Robert Koch became a revolutionary in microbiology. In his postulates, he associates microorganisms with different diseases, and identifies some of them as pathogens. In particular, Koch discovered the bacterium that causes tuberculosis.

If before that protozoa were studied only in general outline, then after 1930, when the first electron microscope was created, science made a leap in this direction. For the first time, a deep study of the structure of microorganisms begins. In 1977, American scientist Carl Wese divides prokaryotes into archaea and bacteria.

Thus, it is safe to say that this discipline is only at the very beginning of its development. Who knows how many more discoveries await us in the coming years.

Structure

Grade 3 already knows firsthand about what bacteria are. Children study the structure of microorganisms in the classroom. Let's go a little deeper into this topic to recover information. Without her, it will be difficult for us to discuss the subsequent points.

The bulk of bacteria consists of only one cell. But it comes in different shapes.

The structure depends on the way of life and food of the microorganism. So there are cocci (round), clostridia and bacilli (rod-shaped), spirochetes and vibrios (sinuous), in the form of cubes, stars and tetrahedrons. It has been noticed that with a minimum amount of nutrients in the environment, bacteria tend to increase their surface area. They grow additional formations. Scientists call these outgrowths "prosthesis".

So, after we have figured out what forms of bacteria are, it is worth touching on them. internal structure... Single-celled microorganisms have a constant set of three structures. Additional elements may vary, but the foundation will always be the same.

So, each bacterium necessarily has an energy structure (nucleotide), non-membrane organelles responsible for protein synthesis from amino acids (ribosomes) and a protoplast. The latter includes the cytoplasm and the cytoplasmic membrane.

From aggressive external influence the cell membrane is protected by a membrane, which consists of a wall, a capsule and a sheath. In some species, surface formations such as villi and flagella are also found. They are designed to help bacteria move effectively in space in order to get food.

Metabolism

It is especially worth dwelling on heterotrophic bacteria. Different types need a certain amount of substances. For example, Bacillus fastidiosus is found only in urine, as it can only get carbon from this acid. We will talk about such microorganisms in more detail later.

Now it is worth dwelling on the methods of replenishing energy in the cell. Modern science knows only three of them. Bacteria use photosynthesis, respiration, or fermentation.

Photosynthesis, in particular, can be both with the use of oxygen and without the participation of this element. Purple, green and heliobacteria do without it. They produce bacteriochlorophyll. For oxygenated photosynthesis, ordinary chlorophyll is required. These include prochlorophytes and cyanobacteria.

A discovery was made recently. Scientists have discovered microorganisms that use hydrogen from the breakdown of water to react in the cell. But that's not all. For this reaction, the presence of uranium ore nearby is necessary, otherwise the required result will not be obtained.

Also, in the deep-sea layers of the world's oceans and at its bottom, there are colonies of bacteria that transmit energy only with the help of an electric current.

Reproduction

Earlier it was said about what bacteria are. We will consider the types of reproduction of these microorganisms now.

There are three methods by which these creatures increase their numbers.

This is sexual reproduction in a primitive form, budding and equal cross-division.

With sexual reproduction, offspring is obtained through transduction, conjugation and transformation.

Place in the world

Earlier, we figured out what bacteria are. Now it's worth talking about the role they play in nature.

The researchers say that bacteria are the first living organisms to appear on our planet. There are both aerobic and anaerobic varieties. Therefore, single-celled creatures are able to survive during various cataclysms that occur with the Earth.

The undoubted benefit of bacteria is the assimilation of atmospheric nitrogen. They are involved in the formation of soil fertility, destruction of the remains of dead flora and fauna. In addition, microorganisms are involved in the creation of minerals and are responsible for maintaining the reserves of oxygen and carbon dioxide in the atmosphere of our planet.

The total biomass of prokaryotes is about five hundred billion tons. More than eighty percent of phosphorus, nitrogen and carbon are stored in it.

However, on Earth there are not only beneficial, but also pathogenic types of bacteria. They cause many fatal diseases. For example, among these are tuberculosis, leprosy, plague, syphilis, anthrax and many others. But even those that are conditionally safe for human life can become a threat with a decrease in the level of immunity.

There are also bacteria that infect animals, birds, fish and plants. Thus, microorganisms are not only in symbiosis with more advanced creatures. Next, we will talk about what pathogenic bacteria are, as well as useful representatives of this type of microorganisms.

Bacteria and humans

We have already figured out what bacteria are, what they look like, what they can do. Now it's worth talking about their role in the life of a modern person.

First, for many centuries we have been using the amazing abilities of lactic acid bacteria. Without these microorganisms, there would be no kefir, no yogurt or cheese in our diet. In addition, such creatures are also responsible for the leavening process.

In agriculture, bacteria are used in two ways. On the one hand, they help to get rid of unnecessary weeds (phytopathogenic organisms, like herbicides), on the other hand, from insects (entomopathogenic unicellular organisms, like insecticides). In addition, humanity has learned to create bacterial fertilizers.

Also, microorganisms are used for military purposes. With the help of various types, deadly biological weapons are created. For this, not only the bacteria themselves are used, but also the toxins released by them.

In a peaceful manner, science uses unicellular organisms for research in genetics, biochemistry, genetic engineering, and molecular biology. With the help of successful experiments, algorithms were created for the synthesis of vitamins, proteins and other substances necessary for a person.

Bacteria are used in other areas as well. With the help of microorganisms, ores are enriched and water bodies and soils are cleaned.

Scientists also say that the bacteria that make up the microflora in the human intestine can be called a separate organ with its own tasks and independent functions. Researchers estimate that there are about one kilogram of these microorganisms inside the body!

In everyday life, we are faced with disease-causing bacteria everywhere. According to statistics, the largest number colonies are located on the handles of supermarket carts, followed by computer mice in Internet cafes, and only in third place are the handles of public latrines.

Beneficial bacteria

Even at school, they teach what bacteria are. Grade 3 knows all sorts of cyanobacteria and other unicellular organisms, their structure and reproduction. Now we will talk about the practical side of the issue.

Half a century ago, no one thought about such a question as the state of the microflora in the intestine. Everything was OK. Eating more natural and healthy, less hormones and antibiotics, less chemical emissions into the environment.

Today, in conditions of poor nutrition, stress, an overabundance of antibiotics, dysbiosis and the problems associated with it are taking the leading positions. How do doctors propose to deal with this?

One of the main answers is the use of probiotics. This is a special complex that repopulates the human intestines with beneficial bacteria.

Such an intervention can help with such unpleasant moments as food allergies, lactose intolerance, gastrointestinal disorders and other ailments.

Let's now touch on what beneficial bacteria are, and also learn about their effect on health.

Three types of microorganisms - acidophilus, Bulgarian bacillus and bifidobacteria - have been studied in most detail and are widely used for a positive effect on the human body.

The first two are designed to stimulate the immune system, as well as reduce the growth of certain harmful microorganisms such as yeast, E. coli, and so on. Bifidobacteria are responsible for digesting lactose, producing certain vitamins, and lowering cholesterol.

Harmful bacteria

Earlier we talked about what bacteria are. The types and names of the most common beneficial microorganisms have been announced above. Further we will focus on the "single-celled enemies" of man.

There are those that are harmful only to humans, there are those that are deadly to animals or plants. People have learned to use the latter, in particular, for the destruction of weeds and annoying insects.

Before delving into what harmful bacteria are, it is worth deciding on the ways of their distribution. And there are a lot of them. There are microorganisms that are transmitted through contaminated and unwashed products, airborne droplets and contact, through water, soil, or through insect bites.

The worst thing is that just one cell, once in the favorable environment of the human body, is capable of multiplying up to several million bacteria within just a few hours.

If we talk about what bacteria are, the names of pathogenic and beneficial ones are difficult to distinguish for a layman. In science, Latin terms are used to designate microorganisms. In common parlance, abstruse words are replaced by the concepts - "Escherichia coli", "causative agents" of cholera, whooping cough, tuberculosis and others.

Preventive measures to prevent disease are of three types. These are vaccinations and vaccines, interruption of transmission routes (gauze dressings, gloves) and quarantine.

Where do bacteria in urine come from?

Some people try to monitor their health and get tested at the clinic. Very often the cause of poor results is the presence of microorganisms in the samples.

We will talk about what bacteria are in the urine a little later. Now it is worth dwelling separately on where, in fact, single-celled creatures appear there.

Ideally, human urine is sterile. There cannot be any foreign organisms. The only way bacteria can enter your excreta is where the waste is excreted from the body. In particular, in this case it will be the urethra.

If the analysis shows a small number of inclusions of microorganisms in the urine, then everything is normal for now. But with an increase in the indicator above the permitted limits, such data indicate the development of inflammatory processes in the genitourinary system. This may include pyelonephritis, prostatitis, urethritis and other unpleasant ailments.

Thus, the question of what bacteria are in the bladder is completely incorrect. Microorganisms do not enter the excreta from this organ. Scientists today identify several reasons leading to the presence of single-celled creatures in the urine.

• First, it is promiscuous sex life.
• Secondly, diseases of the genitourinary system.
• Thirdly, disregard for the rules of personal hygiene.
• Fourth, decreased immunity, diabetes and a number of other disorders.

Types of bacteria in urine

Earlier in the article, it was said that microorganisms in waste products are found only in the case of diseases. We promised to tell you what bacteria are. The names will be given only of those species that are most often found in the test results.

So, let's begin. Lactobacillus is a representative of anaerobic organisms, a gram-positive bacterium. She should be in digestive system person. Its presence in the urine indicates some failures. Such an event is uncritical, however, it is an unpleasant call to the fact that you should seriously take care of yourself.

Proteus is also a natural inhabitant of the gastrointestinal tract. But its presence in the urine indicates a failure in the removal of feces. This microorganism gets into the urine from food only in this way. Signs of the presence of a large amount of proteus in the waste is a burning sensation in the lower abdomen and painful urination with dark color liquids.

Very similar to the previous bacterium is enterococcus fecalis. It enters the urine in the same way, multiplies rapidly and is difficult to treat. In addition, enterococcus microorganisms are resistant to the bulk of antibiotics.

Thus, in this article, we figured out what bacteria are. We talked about their structure and reproduction. You have learned the names of some harmful and beneficial species.

Good luck, dear readers! Remember that following the rules of personal hygiene is the best prevention.

Most people consider different bacterial organisms exclusively as harmful particles that can provoke the development of various pathological conditions. Nevertheless, according to scientists, the world of these organisms is very diverse. There are frankly dangerous bacteria dangerous our body, but there are also useful ones - those that ensure the normal functioning of our organs and systems. Let's try to understand these concepts a little and consider certain types similar organisms. Let's talk about bacteria in nature that are harmful and beneficial to humans.

Beneficial bacteria

Scientists say that bacteria became the very first inhabitants of our large planet, and it is thanks to them that there is life on Earth now. Over the course of many millions of years, these organisms gradually adapted to the constantly changing conditions of existence, they changed their appearance and habitat. The bacteria were able to adapt to the surrounding space and were able to develop new and unique methods of life support, including multiple biochemical reactions - catalysis, photosynthesis, and even seemingly simple respiration. Now bacteria coexist with human organisms, and such cooperation is distinguished by some harmony, because such organisms are capable of bringing real benefits.

After a small person is born, bacteria immediately begin to penetrate into his body. They take root through Airways together with the air, they enter the body along with breast milk, etc. The whole body is saturated with various bacteria.

Their number cannot be accurately calculated, but some scientists boldly say that the number of such cells in an organism is comparable to the number of all cells. The digestive tract alone is home to four hundred different species of living bacteria. It is believed that a certain variety of them can grow only in a specific place. So lactic acid bacteria are able to grow and multiply in the intestines, others feel optimally in the oral cavity, some others live only on the skin.

Over the many years of coexistence, humans and such particles have been able to recreate conditions of cooperation that are optimal for both groups, which can be characterized as a beneficial symbiosis. At the same time, bacteria and our body combine their capabilities, while each side remains in the black.

Bacteria are able to collect particles of various cells on their surface, which is why the immune system does not perceive them as hostile and does not attack. However, after organs and systems are exposed to harmful viruses, beneficial bacteria rise to defense and simply block the path of pathogens. When they exist in the digestive tract, such substances also provide tangible benefits. They are engaged in the processing of food leftovers, while generating a significant amount of heat. It, in turn, is transmitted to nearby organs, and is carried throughout the body.

A deficiency of beneficial bacteria in the body or a change in their number becomes the cause of the development of various pathological conditions. This situation can develop against the background of taking antibiotics, which effectively destroy both harmful and beneficial bacteria. To correct the number of beneficial bacteria, special preparations, probiotics, can be consumed.

Harmful bacteria

However, it is worth remembering that not all bacteria are human friends. Among them, there are also enough dangerous varieties that can only do harm. Such organisms, after penetrating into our body, become the cause of the development of various bacterial ailments. These are various colds, some types of pneumonia, and besides, syphilis, tetanus and other diseases, even deadly ones. There are also diseases of this type, which are transmitted by airborne droplets. This is dangerous tuberculosis, whooping cough, etc.

A significant number of ailments provoked by harmful bacteria develop due to the consumption of insufficient quality food, unwashed and unprocessed vegetables and fruits, raw water, and insufficiently fried meat. You can protect yourself from such diseases by observing the norms and rules of hygiene. An example of such dangerous ailments are dysentery, typhoid fever, etc.

The manifestations of diseases that have developed as a result of an attack by bacteria are the result of the pathological influence of poisons that these organisms produce, or that are formed against the background of their destruction. The human body is able to get rid of them thanks to natural protection, which is based on the process of bacterial phagocytosis by white blood cells, as well as on the immune system, which synthesizes antibodies. The latter carry out a bunch of foreign proteins and carbohydrates, and then simply eliminate them from the bloodstream.

Also, harmful bacteria can be destroyed with the help of natural and synthetic medicines, the most famous of which is penicillin. All drugs of this type are antibiotics, they differ depending on active ingredient and from the scheme of action. Some of them are capable of destroying the cell walls of bacteria, while others stop their vital processes.

So, in nature there is a mass of bacteria that can bring benefits and harm to humans. Fortunately, the modern level of development of medicine makes it possible to cope with the majority of pathological organisms of this kind.

Help me briefly about useful and harmful bacteria all no climbed not worn help pliz

Eternity ............

The risk of bacterial diseases was greatly reduced at the end of the 19th century with the invention of the vaccination method, and in the middle of the 20th century with the discovery of antibiotics.

Useful; For thousands of years, humans have used lactic acid bacteria for the production of cheese, yogurt, kefir, vinegar, and fermentation.

Currently, methods have been developed for the use of phytopathogenic bacteria as safe herbicides, entomopathogenic - instead of insecticides. The most widely used is Bacillus thuringiensis, which secretes toxins (Cry-toxins) that act on insects. In addition to bacterial insecticides, bacterial fertilizers have found application in agriculture.

The bacteria that cause human disease are used as biological weapons.

Due to their rapid growth and reproduction, as well as the simplicity of their structure, bacteria are actively used in scientific research in molecular biology, genetics, genetic engineering, and biochemistry. The best studied bacterium is Escherichia coli. Information about the metabolic processes of bacteria made it possible to produce bacterial synthesis of vitamins, hormones, enzymes, antibiotics, etc.

A promising direction is the enrichment of ores with the help of sulfur-oxidizing bacteria, the purification of soils and water bodies contaminated with oil products or xenobiotics by bacteria.

Normally, the human intestine is inhabited by from 300 to 1000 species of bacteria with a total weight of up to 1 kg, and the number of their cells is an order of magnitude larger than the number of cells in the human body. They play an important role in the digestion of carbohydrates, synthesize vitamins, and displace pathogenic bacteria. We can figuratively say that the human microflora is an additional "organ" that is responsible for protecting the body from infections and digestion.

This is not entirely short. but I think you can shorten it as you like.

Karim Murotaliev

Julia Stoyka

1.Azotobacter (Azotobacter) - enrich the soil with biologically active substances that stimulate plant growth, help cleanse the soil from heavy metals, in particular, from lead and mercury.
2.Bifidobacteria:
supply the body with vitamin K, thiamine (B1), riboflavin (B2), nicotinic acid (B3), pyridoxine (B6), folic acid(B9) amino acids and proteins;
prevent the development of pathogenic microbes;
protect the body from the ingress of toxins from the intestines;
accelerate the digestion of carbohydrates;
activate parietal digestion;
help the absorption of calcium, iron, vitamin D ions through the intestinal wall.
3. Lactic acid bacteria - protect the intestines from putrefactive and pathogenic microbes.
4. Streptomycetes:
are manufacturers (producers) of a wide variety of drugs, including:
antifungal;
antibacterial;

What are bacteria: types of bacteria, their classification

Bacteria are tiny microorganisms that appeared many millennia ago. It is impossible to see microbes with the naked eye, but one should not forget about their existence. There are a huge number of bacilli. Their classification, study, varieties, structural features and physiology are dealt with by the science of microbiology.

Microorganisms are named differently, depending on their kind of action and function. Under a microscope, you can observe how these little creatures interact with each other. The first microorganisms were rather primitive in form, but their importance should in no way be underestimated. From the very beginning, bacilli developed, created colonies, tried to survive in the volatile climatic conditions... Different vibrios are able to exchange amino acids in order to grow and develop normally as a result.

Today it is difficult to say how many species of these microorganisms are on earth (this number exceeds a million), but the most famous and their names are familiar to almost everyone. It doesn't matter what the microbes are and what they are called, they all have one advantage - they live in colonies, so it is much easier for them to adapt and survive.

First, let's figure out what microorganisms exist. The simplest classification is good and bad. In other words, those that harm the human body become the cause of many diseases and those that are beneficial. Next, we will talk in detail about the main useful bacteria and give a description of them.

You can also classify microorganisms according to their shape, characteristics. Probably, many remember that in school textbooks there was a special table with the image of various microorganisms, and side by side was the meaning and their role in nature. There are several types of bacteria:

• cocci - small balls that resemble a chain, as they are located one after another;
• rod-shaped;
• spirillae, spirochetes (have a convoluted shape);
• vibrios.

Bacteria of different forms

We have already mentioned that one of the classifications divides microbes into species depending on their shape.

Coli bacteria also have some characteristics. For example, there are types of rod-shaped ones with pointed poles, with thickened ones, with rounded or straight ends. As a rule, rod-shaped microbes are very different and are always in chaos, they do not line up in a chain (with the exception of streptobacilli), do not attach to each other (except for diplobacilli).

To microorganisms spherical microbiologists include streptococci, staphylococci, diplococci, gonococci. These can be pairs or long chains of balls.

Curved bacilli are spirillae, spirochetes. They are always active, but they do not generate an argument. Spirillae are safe for humans and animals. You can distinguish spirillae from spirochetes if you pay attention to the number of curls, they are less twisted, have special flagella on the limbs.

Types of pathogenic bacteria

For example, a group of microorganisms called cocci, and in more detail streptococci and staphylococci, cause real purulent diseases (furunculosis, streptococcal sore throat).

Anaerobes live and develop well without oxygen; for some types of these microorganisms, oxygen generally becomes lethal. Aerobic microbes need oxygen to live well.

Archaea are practically colorless unicellular organisms.

Pathogenic bacteria need to be wary of, because they cause infections, gram-negative microorganisms are considered resistant to antibodies. There is a lot of information about soil, putrefactive microorganisms, which are harmful, useful.

In general, spirillae are not dangerous, but some species can cause sodoku.

Varieties of beneficial bacteria

Even schoolchildren know that bacilli are useful and harmful. People know some names by ear (staphylococcus, streptococcus, plague bacillus). These are harmful creatures that interfere not only with the external environment, but also with humans. There are microscopic bacilli that cause food poisoning.

Need to know useful information about lactic acid, food, probiotic microorganisms. For example, probiotics, in other words good organisms, are often used for medicinal purposes. You ask: for what? They prevent harmful bacteria from multiplying inside a person, strengthen the protective functions of the intestines, and have a good effect on the human immune system.

Bifidobacteria are also very beneficial for the intestines. Lactic acid vibrios include about 25 species. In the human body, they are found in huge quantities, but they are not dangerous. On the contrary, they protect the gastrointestinal tract from putrefactive and other microbes.

Speaking of the good ones, one cannot fail to mention the huge species of streptomycetes. They are known to those who took chloramphenicol, erythromycin and similar drugs.

There are microorganisms such as azotobacters. They live in soils for many years, have a beneficial effect on the soil, stimulate plant growth, and cleanse the earth of heavy metals. They are irreplaceable in medicine, agriculture, medicine, food industry.

Types of bacterial variability

By their nature, microbes are very fickle, they die quickly, they can be spontaneous, induced. We will not go into details about the variability of bacteria, since this information is more interesting for those who are interested in microbiology and all its branches.

Types of bacteria for septic tanks

Residents of private houses understand the urgent need to treat wastewater, as well as cesspools. Today, drains can be quickly and efficiently cleaned with the help of special bacteria for septic tanks. For a person, this is a huge relief, since cleaning the sewers is not a pleasant thing.

We have already clarified where it is applied biological species sewage treatment, and now let's talk about the system itself. Bacteria for septic tanks are grown in laboratories, they kill the unpleasant odor of sewage, disinfect drainage wells, cesspools, and reduce the volume of wastewater. There are three types of bacteria that are used for septic tanks:

• aerobic;
• anaerobic;
• live (bioactivators).

Very often people use combined cleaning methods. Strictly follow the instructions on the preparation, make sure that the water level is conducive to the normal survival of bacteria. Also, remember to use the drain at least once every two weeks to give the bacteria something to eat or they will die. Remember that chlorine from powders and cleaning fluids will kill bacteria.

The most popular bacteria are Dr. Robik, Septifos, Waste Treat.

Types of bacteria in urine

In theory, there should be no bacteria in the urine, but after various actions and situations, tiny microorganisms settle wherever they please: in the vagina, in the nose, in water, and so on. If bacteria are found during the tests, this means that the person is suffering from kidney, bladder or ureteral diseases. There are several ways in which microorganisms enter the urine. Before treatment, it is very important to investigate and accurately determine the type of bacteria and the route of entry. This can be determined by biological culture of urine, when bacteria are placed in a favorable habitat. Next, the reaction of bacteria to various antibiotics is checked.

We wish you to remain always healthy. Take care of yourself, wash your hands regularly, protect your body from harmful bacteria!

The beneficial bacteria that inhabit the human body are called microbiota. In terms of their numbers, they are quite extensive - one person has millions of them. Moreover, they all regulate the health and normal life of each individual. Scientists say: without beneficial bacteria, or, as they are also called, mutualists, the gastrointestinal tract, skin, respiratory tract would be instantly attacked by pathogenic microbes and would be destroyed.

What should be the balance of microbiota in the body and how it can be adjusted to avoid development serious illnesses, AiF.ru asked General Director of the biomedical holding Sergey Musienko.

Bowel workers

One of the important sections of the location of beneficial bacteria is the intestine. It is not without reason that it is believed that it is here that all the immune system person. And if the bacterial environment is disturbed, then the body's defenses are significantly reduced.

Beneficial intestinal bacteria create literally unbearable living conditions for pathogenic microbes - an acidic environment. In addition, beneficial microorganisms help digest vegetable food, since bacteria feed on plant cells containing cellulose, but intestinal enzymes alone cannot cope with this. Gut bacteria also contribute to the production of vitamins B and K, which support the metabolism of bones and connective tissues, as well as release energy from carbohydrates and promote antibody synthesis and regulation nervous system.

Most often, speaking of beneficial intestinal bacteria, they mean the 2 most popular types: bifidobacteria and lactobacilli. At the same time, it is impossible to call them the main ones, as many people think - their number is only 5-15% of the total. However, they are very important, since they have been proven positive influence to other bacteria, when such bacteria can be important factors in the well-being of the whole community: if they are fed or introduced into the body with the help of fermented milk products - kefir or yoghurts, they help other important bacteria to survive and multiply. So, for example, it is very important to restore their population with dysbiosis or after a course of taking antibiotics. Otherwise, it will be problematic to increase the body's defenses.

Biological shield

The bacteria that inhabit the skin and respiratory tract of a person, in fact, stand guard and reliably protect their area of ​​responsibility from the penetration of pathogens. The main ones are micrococci, streptococci and staphylococci.

The microbiome of the skin has undergone changes over the past hundreds of years, as humans have moved from natural life in contact with nature to regular washing with special means. It is believed that now the human skin is inhabited by completely different bacteria that lived before. The body, with the help of the immune system, can distinguish between dangerous and non-dangerous. But, on the other hand, any streptococcus can become pathogenic for humans, for example, if it gets into a cut or any other open wound on the skin. An excess of bacteria or their pathological activity on the skin and in the respiratory tract can lead to both the development of various diseases and the appearance bad smell... Today there are developments based on bacteria that oxidize ammonium. Their use allows to inoculate the skin microbiome with completely new organisms, as a result of which not only the smell disappears (the result of the metabolism of urban flora), but also the structure of the skin changes - pores open, etc.

Salvation of the microcosm

The microcosm of each person is changing quite quickly. And this has undoubted advantages, since the number of bacteria can be renewed independently.

Different bacteria feed on different substances - the more diverse a person's food is and the more it corresponds to the season, the more choice beneficial microorganisms have. However, if the food is richly filled with antibiotics or preservatives, bacteria will not survive, because these substances are precisely created in order to destroy them. Moreover, it does not matter at all that most of the bacteria are not pathogenic. As a result, the diversity of a person's inner world is destroyed. And after this, various diseases begin - problems with stools, skin rashes, metabolic disorders, allergic reactions etc.

But the microbiota can be helped. Moreover, it will take only a few days for a light correction.

There are a large number of probiotics (with live bacteria) and prebiotics (substances that support bacteria). But the main problem is that they work differently for everyone. Analysis shows that their effectiveness in dysbiosis is up to 70-80%, that is, this or that drug may or may not work. And here you should carefully monitor the course of treatment and reception - if the funds work, you will immediately notice improvements. If the situation remains unchanged, it is worth changing the treatment program.

Alternatively, you can undergo special testing, which studies the genomes of bacteria, determines their composition and ratio. This allows you to quickly and competently select the necessary nutritional option and additional therapy that will restore the delicate balance. Although a person does not feel slight disturbances in the balance of bacteria, they still affect health - in this case, frequent illnesses, drowsiness, allergic manifestations... Every resident of the city has an imbalance in the body to one degree or another, and if he does not do anything specifically to recover, then surely from a certain age he will have health problems.

Fasting, unloading, more vegetables, cereal porridge in the morning - these are just a few of the eating behaviors that beneficial bacteria love. But for each person, the diet should be individual in accordance with the state of his body and his lifestyle - only then he will be able to maintain an optimal balance and always feel good.

Bacteria appeared about 3.5-3.9 billion years ago, they were the first living organisms on our planet. Over time, life developed and became more complicated - new, each time more complex forms of organisms appeared. Bacteria all this time did not stand aside, on the contrary, they were the most important component of the evolutionary process. They were the first to develop new forms of life support, such as respiration, fermentation, photosynthesis, catalysis ... and also found effective ways to coexist with almost every living creature. Man was not an exception either.

But bacteria are a whole domain of organisms with over 10,000 species. Each species is unique and went its own evolutionary path, as a result, developed its own unique forms of coexistence with other organisms. Some bacteria have gone to close mutually beneficial cooperation with humans, animals and other creatures - they can be called useful. Other species have learned to exist at the expense of others, using the energy and resources of donor organisms - they are considered to be harmful or pathogenic. Still others went even further and became practically self-sufficient, they receive everything they need for life from the environment.

Inside humans, as well as inside other mammals, an unimaginably large number of bacteria live. There are 10 times more of them in our bodies than all the cells of the body put together. The absolute majority of them are useful, but the paradox is that their vital activity, their presence inside us is a normal state of affairs, they depend on us, we, in turn, on them, and at the same time we do not feel any signs of this cooperation. Another thing is harmful, for example, pathogenic bacteria, once inside us, their presence immediately becomes noticeable, and the consequences of their activity can become very serious.

Beneficial bacteria

The vast majority of them are creatures living in symbiotic or mutualistic relationships with donor organisms (inside of which they live). Typically, these bacteria take on some of the functions that the host's body is not capable of. An example is bacteria that live in the human digestive tract and process part of the food that the stomach itself is not able to handle.

Some types of beneficial bacteria:

Escherichia coli (lat.Escherichia coli)

It is an integral part of the intestinal flora of humans and most animals. Its benefits can hardly be overestimated: it breaks down indigestible monosaccharides, facilitating digestion; synthesizes vitamins of group K; prevents the development of pathogenic and pathogenic microorganisms in the intestines.

Closeup: colony of Escherichia coli bacteria

Lactic acid bacteria (Lactococcus lactis, Lactobacillus acidophilus, etc.)

Representatives of this order are present in milk, dairy and fermented products, and at the same time are part of the intestinal and oral microflora. They are able to ferment carbohydrates and in particular lactose and produce lactic acid, which is the main source of carbohydrates for humans. By maintaining a constant acidic environment, the growth of unfavorable bacteria is suppressed.

Bifidobacteria

The most significant effect of bifidobacteria is exerted on infants and mammals, accounting for up to 90% of their intestinal microflora. By means of the production of lactic and acetic acids, they completely prevent the development of putrefactive and pathogenic microbes in the child's body. In addition, bifidobacteria: facilitate the digestion of carbohydrates; provide protection of the intestinal barrier from the penetration of microbes and toxins into the internal environment of the body; synthesize various amino acids and proteins, vitamins of group K and B, useful acids; promote intestinal absorption of calcium, iron and vitamin D.

Harmful (pathogenic) bacteria

Some types of pathogenic bacteria:

Salmonella typhi

This bacterium is the causative agent of a very acute intestinal infection, typhoid fever. Salmonella typhi produces toxins that are dangerous exclusively to humans. When infected, a general intoxication of the body occurs, which leads to severe fever, a rash all over the body, in severe cases to damage to the lymphatic system and, as a result, to death. Every year 20 million cases of typhoid fever are recorded in the world, 1% of cases lead to death.

Colony of bacteria Salmonella typhi

Tetanus stick (Clostridium tetani)

This bacterium is one of the most persistent and at the same time the most dangerous in the world. Clostridium tetani produces an extremely toxic poison, the tetanus exotoxin, which causes almost complete damage to the nervous system. People with tetanus experience terrible torment: all the muscles of the body spontaneously strain to the limit, and powerful convulsions occur. The mortality rate is extremely high - on average, about 50% of those infected die. Fortunately, back in 1890, the tetanus vaccine was invented, it is made to newborns in all developed countries of the world. In underdeveloped countries, 60,000 people die from tetanus every year.

Mycobacterium (Mycobacterium tuberculosis, Mycobacterium leprae, etc.)

Mycobacteria are a family of bacteria, some of which are pathogenic. Various representatives of this family cause such dangerous diseases as tuberculosis, mycobacteriosis, leprosy (leprosy) - all of which are transmitted by airborne droplets. Mycobacteria cause more than 5 million deaths every year.

Bacteria are dangerous and useful, their role in human life

Bacterial infections are considered one of the most dangerous - humanity has been fighting against pathogenic microorganisms for more than one century. However, not all bacteria are unambiguous enemies for humans. Many species are vital - they provide proper digestion and even help the immune system to defend itself against other microorganisms. MedAboutMe will tell you how to distinguish between good and bad bacteria, what to do if they are found in the analysis, and how to properly treat the diseases caused by them.

Bacteria and humans

It is believed that bacteria appeared on Earth over 3.5 billion years ago. They have become active participants in creating suitable conditions for life on the planet, and throughout their existence have been actively involved in important processes. For example, it is thanks to bacteria that the decay of organic remains of animals and plants occurs. They also created fertile soil on Earth.

And since bacteria live literally everywhere, the human body is no exception. On the skin, mucous membranes, in the gastrointestinal tract, nasopharynx, urogenital tract, there are many microorganisms that interact with humans in different ways.

In the womb, the placenta protects the fetus from the penetration of bacteria, the population of the body by them occurs in the first days of life:

• The first bacteria the child receives when passing through birth canal mother.
• Microorganisms enter the gastrointestinal tract when feeding with breast milk. Here, among more than 700 species, lacto- and bifidobacteria predominate (the benefits are described in the table of bacteria at the end of the article).
• The oral cavity is inhabited by staphylococci, streptococci and other microbes, which the child also receives from food and from contact with objects.
• On the skin, microflora is formed from bacteria that prevail in the people around the child.

The role of bacteria for a person is invaluable, if already in the first months the microflora does not form normally, the child will lag behind in development and often get sick. Indeed, without symbiosis with bacteria, the body cannot function.

Good and bad bacteria

Everyone is well aware of the concept of dysbiosis - a condition in which the natural microflora in the human body is disrupted. Dysbacteriosis is a serious factor in lowering immune defense, the development of various inflammations, disruption of the gastrointestinal tract and other things. The absence of beneficial bacteria contributes to the multiplication of pathogenic organisms, and fungal infections often develop against the background of dysbiosis.

Moreover, the environment is home to many pathogenic microbes that can cause serious illnesses... The most dangerous are those types of bacteria that, in the process of their vital activity, are capable of producing toxins (exotoxins). It is these substances that are considered today one of the most powerful poisons. Such microorganisms cause dangerous infections:

• Botulism.
• Gas gangrene.
• Diphtheria.
• Tetanus.

In addition, the disease can also be provoked by bacteria, which under normal conditions live in the human body, and when the immunity is weakened, they begin to activate. The most popular pathogens of this kind are staphylococci and streptococci.

Bacteria life

Bacteria are full-fledged living organisms 0.5-5 microns in size, which are able to actively reproduce in a suitable environment. Some of them need oxygen, others do not. There are mobile and non-mobile types of bacteria.

Bacteria cell

Most bacteria living on Earth are single-celled organisms. Mandatory components of any microbe:

• Nucleoid (a nucleus-like region containing DNA).
• Ribosomes (carry out protein synthesis).
• Cytoplasmic membrane (separates the cell from the external environment, maintains homeostasis).

Also, some bacterial cells have a thick cell wall, which additionally protects them from damage. Such organisms are more resistant to drugs and antigens produced by the human immune system.

There are bacteria with flagella (mototrichia, lophotrichia, peritrichia), due to which microorganisms are able to move. However, scientists have recorded another type of movement that is characteristic of microbes - the sliding of bacteria. Moreover, recent studies show that it is inherent in those species that were previously considered immobile. For example, scientists from the Universities of Nottingham and Sheffield have shown that methicillin-resistant Staphylococcus aureus (one of the main representatives of the superbug class) can move without the help of flagella and villi. And this, in turn, significantly affects the understanding of the mechanisms of the spread of a dangerous infection.

Bacterial cells can be of the following forms:

• Round (cocci, from ancient Greek. Κόκκος - "grain").
• Rod-shaped (bacilli, clostridia).
• Sinuous (spirochetes, spirillae, vibrios).

Many microorganisms are capable of sticking together in a colony, therefore, more often scientists and doctors isolate bacteria not by the structure of the element, but by the type of compounds:

• Diplococci are cocci connected in pairs.
• Streptococci are cocci that form chains.
• Staphylococci are cocci that form clusters.
• Streptobacteria are rod-shaped microorganisms connected in a chain.

Reproduction of bacteria

The vast majority of bacteria multiply by division. The rate of spread of the colony depends on the external conditions and the type of microorganism itself. So, on average, one bacterium is able to divide every 20 minutes - it forms 72 generations of offspring per day. In 1-3 days, the number of descendants of one microorganism can reach several million. At the same time, the multiplication of bacteria may not be so fast. For example, the process of dividing Mycobacterium tuberculosis takes 14 hours.

If bacteria enter a favorable environment and have no competitors, the population grows very quickly. Otherwise, other microorganisms regulate its number. That is why the human microflora is an essential factor in its protection against various infections.

Bacterial spores

One of the features of rod-shaped bacteria is their ability to sporulate. These microorganisms are called bacilli and include the following pathogenic bacteria:

• The genus Clostridium (cause gas gangrene, botulism, often cause complications during childbirth and after abortion).
• Genus bacillus (cause anthrax, a number of food poisoning).

Bacterial spores are, in fact, a conserved cell of a microorganism, which is able to persist for a long time without damage, practically not subject to various influences. In particular, spores are thermally stable, not damaged by chemicals. Often the only possible impact is ultra-violet rays under which dried bacteria can die.

Bacterial spores form when the microorganism is exposed to unfavorable conditions. It takes about 18-20 hours to form inside the cell. At this time, the bacterium loses water, decreases in size, becomes lighter, and a dense shell forms under the outer membrane. In this form, the microorganism can freeze for hundreds of years.

When the bacterial spore is in the right conditions, it begins to germinate into a viable bacterium. The process takes about 4-6 hours.

Types of bacteria

According to the effect of bacteria on humans, they can be divided into three types:

• Pathogenic.
• Conditionally pathogenic.
• Non-pathogenic.

Beneficial bacteria

Non-pathogenic bacteria are those that never cause disease, even if their numbers are large enough. Among the most famous species are lactic acid bacteria, which are actively used by humans in the food industry - for the preparation of cheeses, fermented milk products, dough and much more.

Another important species is bifidobacteria, which are the basis of the intestinal flora. In babies on breastfeeding they account for up to 90% of all species living in the gastrointestinal tract. These bacteria perform the following functions for humans:

• Provide physiological protection of the intestine from the penetration of pathogenic organisms.
• Produce organic acids that prevent the growth of pathogenic microbes.
• They help to synthesize vitamins (K, group B), as well as proteins.
• Enhances the absorption of vitamin D.

It is difficult to overestimate the role of bacteria of this species, because without them normal digestion is impossible, and hence the assimilation of nutrients.

Conditionally pathogenic bacteria

A healthy microflora contains bacteria that are classified as conditionally pathogenic. These microorganisms can exist for years on the skin, in the nasopharynx or intestines of a person and not cause infections. However, under any favorable conditions (weakening of immunity, disturbance of microflora), their colony grows and becomes a real threat.

A classic example of an opportunistic bacterium is Staphylococcus aureus, a microbe that can cause more than 100 different diseases, from boils on the skin to fatal blood poisoning (sepsis). Moreover, in most people in various analyzes, this bacterium is found, but still does not cause illness.

Among other representatives of the species of opportunistic microbes:

• Streptococci.
• Escherichia coli.
• Helicobacter pylori (can cause ulcers and gastritis, but in 90% of people it lives as part of a healthy microflora).

It makes no sense to get rid of these types of bacteria, since they are widespread in the environment. The only one in an adequate way prevention of infections is to strengthen the immune system and protect the body from dysbiosis.

Pathogenic bacteria behave differently - their presence in the body always means the development of an infection. Even a small colony can be harmful. Most of these microorganisms secrete two types of toxins:

• Endotoxins are poisons formed when cells are destroyed.
• Exotoxins are poisons that a bacterium produces during its life. The most dangerous substances for humans that can lead to fatal intoxication.

Treatment of such infections is aimed not only at destroying pathogenic bacteria, but also at removing the poisoning caused by them. Moreover, in the case of infection with microbes such as tetanus bacillus, it is the administration of toxoid that is the basis of therapy.

Other known pathogenic bacteria include:

• Salmonella.
• Pseudomonas aeruginosa.
• Gonococcus.
• Pale treponema.
• Shigella.
• Tuberculosis bacillus (Koch's stick).

Classes of bacteria

There are many classifications of bacteria today. Scientists divide them according to the type of structure, the ability to move and other features. However, the most important are the Gram classifications and the type of breathing.

Anaerobic and aerobic bacteria

Among the whole variety of bacteria, two large classes are distinguished:

• Anaerobic - those that are able to do without oxygen.
• Aerobic - those that need oxygen to function.

A feature of anaerobic bacteria is their ability to live in environments where other microorganisms cannot survive. The most dangerous in this regard are deeply contaminated wounds, in which microbes develop rapidly. The characteristic signs of the growth of the population and the life of bacteria in the human body are as follows:

• Progressive tissue necrosis.
• Subcutaneous suppuration.
• Abscesses.
• Internal lesions.

Anaerobes include pathogenic bacteria that cause tetanus, gas gangrene, toxic lesions of the gastrointestinal tract. Also, the anaerobic class of bacteria includes many opportunistic microbes that live on the skin and in the intestinal tract. They become dangerous if they fall into an open wound.

To the aerobic class of bacteria, disease-causing relate:

• Tuberculosis bacillus.
• Cholera vibrio.
• Tularemia stick.

The life of bacteria can proceed even with a small amount of oxygen. Such microbes are called facultatively aerobic, salmonella and cocci (streptococcus, staphylococcus) are a prime example of the group.

In 1884, Danish physician Hans Gram discovered that different bacteria stain differently when exposed to methylene violet. Some retain their color after washing, while others lose it. Based on this, the following classes of bacteria were identified:

• Gram-negative (Gram−) - discolored.
• Gram positive (Gram +) - staining.

Staining with aniline dyes is a simple technique that makes it possible to quickly reveal the characteristics of the bacterial membrane wall. For those microbes that do not stain according to Gram, it is more powerful and durable, which means that it is more difficult to fight them. Gram-negative bacteria, first of all, are more resistant to antibodies produced by the human immune system. This class includes microbes that cause such diseases:

• Syphilis.
• Leptospirosis.
• Chlamydia
• Meningococcal infection.
• Hemophilic infection
• Brucellosis.
• Legionellosis.

The Gram + class of bacteria includes the following microorganisms:

• Staphylococcus aureus.
• Streptococcus.
• Clostridia (causative agents of botulism and tetanus).
• Listeria.
• Diphtheria bacillus.

Diagnosis of bacterial infections

Correct and timely diagnosis plays an important role in the treatment of bacterial infections. It is possible to accurately determine the disease only after an analysis, however, it can already be suspected by its characteristic symptoms.

Bacteria and viruses: characteristics of bacteria and differences in infections

Most often, a person is faced with acute respiratory diseases. Usually cough, rhinitis, elevated temperature and sore throats are caused by bacteria and viruses. And although at certain stages of the disease they can manifest themselves in the same way, their therapy will still be radically different.

Bacteria and viruses behave differently in the human body:

• Bacteria are full-fledged living organisms, large enough (up to 5 microns), capable of reproducing in a suitable environment (on mucous membranes, skin, in wounds). Pathogenic microbes secrete poisons that lead to intoxication. The same bacteria can cause infections in different locations. For example, Staphylococcus aureus affects the skin, mucous membranes, and can lead to blood poisoning.
• Viruses are non-cellular infectious agents capable of multiplying only inside a living cell, and in the external environment they do not manifest themselves as living organisms. Moreover, viruses are always highly specialized and can infect only a specific type of cells. For example, hepatitis viruses can only infect the liver. Viruses are much smaller than bacteria, their size does not exceed 300 nm.

Today developed against bacteria effective drugs-. But these drugs do not work on viruses, moreover, according to the World Health Organization, antibiotic therapy for ARVI worsens the patient's condition.

Symptoms of bacterial infections

Most often, seasonal respiratory infections develop under the influence of bacteria and viruses in the following way:

• The first 4-5 days is manifested viral infection.
• On the 4-5th day, if the rules for treating ARVI were not followed, a bacterial lesion joins.

Symptoms of a bacterial infection in this case will be:

• Deterioration of the patient's condition after improvement.
• High temperature (38 ° C and above).
• Severe chest pain (a sign of pneumonia).
• Discoloration of mucus - greenish, white, or yellowish discharge from the nose and coughing up sputum.
• Rash on the skin.

If it is possible to treat without the involvement of a doctor, since a viral infection passes without complications on its own in 4-7 days, then diseases caused by pathogenic bacteria necessarily require the consultation of a therapist or pediatrician.

With other bacterial infections, the following symptoms are characteristic:

• General worsening of the condition.
• A pronounced inflammatory process - pain in the affected area, hyperemia, fever.
• Suppuration.

Modes of transmission of bacterial infections

Harmful bacteria enter the human body different ways... The most common routes of infection are:

• Airborne.

The bacteria are in the exhaled air, the sputum of the patient, spread by coughing, sneezing and even talking. This route of transmission is typical for respiratory infections, in particular, whooping cough, diphtheria, scarlet fever.

• Contact and household.

Microbes get to a person through dishes, door handles, furniture surfaces, towels, phones, toys, and more. Also, live bacteria and bacterial spores can be in the dust for a long time. This is how tuberculosis, diphtheria, dysentery, diseases caused by aureus and other types of staphylococcus are transmitted.

• Alimentary (fecal-oral).

Bacteria enter the body through contaminated food or water. The route of transmission is typical for gastrointestinal infections, in particular, typhoid fever, cholera, dysentery.

• Sexual.

Infection occurs during intercourse, which is how STIs, including syphilis and gonorrhea, are transmitted.

• Vertical.

The bacteria is passed on to the fetus during pregnancy or childbirth. So a child can become infected with tuberculosis, syphilis, leptospirosis.

Deep wounds are dangerous for the development of infections - it is here that anaerobic bacteria, including tetanus bacillus, actively multiply. Also, the likelihood of contracting a bacterial infection increases in people with weakened immune systems.

If you suspect the presence of pathogenic bacteria, the doctor may offer the following diagnostic options:

• A smear for flora.

If a respiratory infection is suspected, it is taken from the mucous membranes of the nose and throat. Also, the analysis is popular for detecting sexually transmitted infections. In this case, the material is taken from the vagina, visceral canal, urethra.

• Bacteriological culture.

It differs from a smear in that the taken biomaterial is not examined immediately, but is placed in an environment favorable for the reproduction of bacteria. After a few days or weeks, depending on the suspected pathogen, the result is assessed - if there were harmful bacteria in the biomaterial, they grow into a colony. Bacterial culture is also good in that during the analysis, not only the pathogen is determined, but also its quantity, as well as the sensitivity of the microbe to antibiotics.

• Blood test.

A bacterial infection can be detected by the presence of antibodies, antigens in the blood and by the leukocyte formula.

Today, biomaterial is often examined by PCR (polymerase chain reaction), in which it is possible to detect an infection even with a small number of microbes.

Positive test and bacterial infections

Since many bacteria are conditionally pathogenic and at the same time live in the body, on the mucous membranes and skin of most of the population, the results of the analysis must be able to correctly interpret. It must be remembered that the very presence of bacteria in a person is not a sign of a bacterial infection and is not a reason to start treatment. For example, 103-104 is considered the norm for Staphylococcus aureus. With such indicators, no therapy is required. Moreover, since the microflora of each person is individual, even if the values ​​are higher, but there will be no symptoms of the disease, the indicators can also be considered the norm.

An analysis for different types of bacteria is prescribed if there are signs of infection:

• Feeling unwell.
• Purulent discharge.
• Inflammatory process.
• Greenish, white, or yellow mucus from nose and in expectoration.

Positive analysis bacteria in the absence of symptoms is taken for control if microbes are detected in people from risk groups: pregnant women, children, people in the postoperative period, patients with reduced immunity and concomitant diseases. In this case, it is recommended to pass several tests to see the dynamics of the growth of the colony. If the values ​​do not change, then the immune system is able to control the growth of bacteria.

Bacteria in the nasopharynx

Bacteria in the nasopharynx can cause respiratory tract infections. In particular, they are the cause of sore throat, bacterial tonsillitis and pharyngitis, as well as sinusitis. Neglected infections can cause many inconveniences, chronic inflammatory processes, persistent rhinitis, headaches and more. Such diseases are especially dangerous because harmful bacteria can descend through the respiratory tract and infect the lungs - cause pneumonia.

Bacteria in urine

Ideally, it is the urine that should be free of various microorganisms. The presence of bacteria in the urine may indicate an incorrectly passed analysis (in which microbes got into the material from the surface of the skin and mucous membranes), in which case the doctor asks to undergo the examination again. If the result is confirmed, and the indicator exceeds 104 CFU / ml, bacteriuria (bacteria in the urine) indicates the following diseases:

• Kidney damage, in particular, pyelonephritis.
• Cystitis.
• Urethritis.
• Inflammatory process in the urinary tract, for example, as a result of blocking it with calculus. It is observed with urolithiasis.
• Prostatitis or prostate adenoma.

In some cases, bacteria in the urine are found in diseases not associated with local infection. A positive test can be in diabetes mellitus, as well as generalized lesions - sepsis.

Normally, the gastrointestinal tract is inhabited by colonies of various bacteria. In particular, there are:

• Bifidobacteria.
• Lactic acid bacteria (lactobacilli).
• Enterococci.
• Clostridia.
• Streptococci.
• Staphylococci.
• Escherichia coli.

The role of bacteria that make up normal microflora, - protecting the intestines from infections and ensuring normal digestion. Therefore, biomaterial from the intestine is often examined precisely because of suspicion of dysbiosis, and not for the presence of pathogenic microorganisms.

However, some pathogenic bacteria can cause serious illnesses, it is when it enters the digestive tract. Among such diseases:

• Salmonellosis.
• Cholera.
• Botulism.
• Dysentery.

Bacteria on the skin

On the skin, as well as on the mucous membranes of the nasopharynx, in the intestines and genitals, the microflora balance is normally established. Bacteria live here - more than 100 species, among which epidermal and Staphylococcus aureus, streptococci are often found. With reduced immunity, and especially in children, they can provoke skin lesions, cause suppuration, boils and carbuncles, streptoderma, panaritium and other diseases.

During adolescence, the active multiplication of bacteria leads to acne and acne.

The main danger of microbes on the skin is the possibility of their entering the bloodstream, wounds and other damage to the epidermis. In this case, harmless microorganisms on the skin can cause serious illness even cause sepsis.

Diseases caused by bacteria

Bacteria are the cause of infections throughout the body. They affect the respiratory tract, cause inflammation of the skin, cause diseases of the intestines and genitourinary system.

Diseases of the respiratory tract and lungs

Angina

Angina is an acute lesion of the tonsils. The disease is typical for childhood.

Causative agent:

• Streptococci, less often staphylococci and other forms of bacteria.

Typical symptoms:

• inflammation of the tonsils with a whitish coating on them, pain when swallowing, hoarseness, high fever, absence of rhinitis.

Danger of illness:

• if angina is not treated well enough, rheumatoid heart disease can become its complication - harmful bacteria spread through the blood and lead to heart valve defects. As a result, heart failure can develop.

Whooping cough is a dangerous infectious disease that mainly affects children. It is highly contagious, the bacterium is transmitted by airborne droplets, therefore, without a sufficient level of immunization of the population, it can easily cause epidemics.

Causative agent:

• Bordetella pertussis.

Typical symptoms:

• the disease initially proceeds like a common cold, later a characteristic paroxysmal barking cough appears, which may not go away for 2 months, after an attack the child may vomit.

Danger of illness:

• whooping cough is most dangerous for children in the first year of life, as it can cause respiratory arrest and death. Typical complications are pneumonia, bronchitis, false croup... From severe attacks of coughing extremely rarely, cerebral hemorrhage or pneumothorax can occur.

Pneumonia

Lung inflammation can be caused by bacteria and viruses, as well as some fungi. Bacterial pneumonia, the most common complication of viral respiratory infections, can develop after influenza. Also, the multiplication of bacteria in the lungs is characteristic of bedridden patients, the elderly, patients with chronic lung diseases and respiratory disorders, and dehydration.

Causative agent:

• Staphylococci, pneumococci, Pseudomonas aeruginosa and others.

Typical symptoms:

• a strong increase in temperature (up to 39 ° C and above), cough with abundant moist greenish or yellowish sputum, chest pain, shortness of breath, feeling short of breath.

Danger of illness:

• depends on the pathogen. With insufficient treatment, respiratory arrest and death are possible.

Tuberculosis

Tuberculosis is one of the most dangerous lung diseases that is difficult to treat. Since 2004, tuberculosis has been a socially significant disease in Russia, since the number of infected people is much higher than in developed countries. Back in 2013, up to 54 cases of infection were recorded per 100 thousand people.

Causative agent:

• mycobacterium, Koch's bacillus.

Typical symptoms:

• the disease may not manifest itself for a long time, after a cough occurs, general malaise, a person loses weight, there is subfebrile temperature(37-38 ° C) for a month or more, painful blush. Hemoptysis and severe pain later appear.

Danger of illness:

• the characteristics of the bacteria that cause tuberculosis are the development of antibiotic resistance. Therefore, the infection is difficult to treat and can lead to death or disability. Frequent complications- heart disease.

Diphtheria is an infectious disease that affects the upper respiratory tract in 90% of cases. Diphtheria is especially dangerous for young children.

Causative agent:

• Corynebacterium diphtheriae (Leffler's bacillus).

Typical symptoms:

• pain when swallowing, hyperemia of the tonsils and specific white films on them, enlarged lymph nodes, shortness of breath, high fever, general intoxication of the body.

Danger of illness:

• without timely treatment diphtheria is fatal. The bacterial cell is capable of producing exotoxin, so the sick person can die from poisoning, which affects the heart and nervous system.

Intestinal infections

Salmonellosis

Salmonellosis is one of the most common intestinal infections that can take many forms. Sometimes bacteria cause severe damage, but there are times when the disease goes away in mild form or no symptoms at all.

Causative agent:

• Salmonella.

Typical symptoms:

• high temperature (up to 38-39 ° C), chills, abdominal pain, vomiting, diarrhea, severe intoxication of the body, in which a person weakens sharply.

Danger of illness:

• Depends on the form of the course; in severe infection, bacterial toxins can lead to renal failure or peritonitis. Dehydration is dangerous for children.

Dysentery

Dysentery is an intestinal infection that affects people of all ages. Most often recorded during the hot summer period.

Causative agent:

• 4 types of Shigella bacteria.

Typical symptoms:

• Liquid, dark green stools with blood and pus, nausea, headaches, loss of appetite.

Danger of illness:

• dehydration, which leads to the addition of various inflammations, as well as intoxication of the body. With proper treatment, good immunity and sufficient fluid intake, the life of Shigella bacteria ends in 7-10 days. Otherwise it is possible severe complication- intestinal perforation.

Gonorrhea

Gonorrhea is transmitted exclusively through sexual contact, but in rare cases, the infection can pass from mother to child during childbirth (the baby develops conjunctivitis). The bacteria that cause gonorrhea may multiply in the anus or throat, but most often the disease affects the genitals.

Causative agent:

• Gonococcus.

Typical symptoms:

• possibly asymptomatic course of the disease: in men - 20%, in women - more than 50%. In the acute form, there is pain during urination, white-yellow discharge from the penis and vagina, burning and itching.

Danger of illness:

• if the infection is not treated, it can cause infertility, as well as lead to damage to the skin, joints, of cardio-vascular system, liver and brain.

Syphilis

Syphilis has a slow progression, symptoms appear gradually and do not develop quickly. The characteristic course of the disease is the alternation of exacerbations and remissions. Household infection, many doctors question, in the overwhelming majority of cases, bacteria are sexually transmitted to humans.

Causative agent:

• Pale treponema.

Typical symptoms:

• at the first stage, an ulcer develops on the genitals, which heals on its own in 1-1.5 months, an increase in lymph nodes is observed. After, after 1-3 months, a pale rash appears all over the body, the patient feels weak, the temperature may rise, the symptoms resemble the flu.

Danger of illness:

• pathogenic bacteria eventually lead to the development of tertiary syphilis (30% of all infected), which affects the aorta, brain and back, bones and muscles. Perhaps the development of damage to the nervous system - neurosyphilis.

Chlamydia

Chlamydia is a sexually transmitted infection that is often asymptomatic. In addition, pathogenic bacteria are difficult to detect; PCR analysis is prescribed for diagnosis.

Causative agent:

• Chlamydia.

Typical symptoms:

• in the acute form, discharge from the genitals (usually transparent), pain during urination, and bleeding are observed.

Danger of illness:

• in men - inflammation of the epididymis, in women - inflammation of the uterus and appendages, infertility, Reiter's syndrome (inflammation of the urethra).

Meningococcal infection

Meningococcal infection is a group of diseases caused by one pathogen, but occurring in different form... A person may be an asymptomatic carrier of the bacterium, and in other cases, the microbe causes a generalized infection, leading to death.

Causative agent:

• Meningococcus.

Typical symptoms:

• vary with the severity of the disease. The infection can manifest itself as a mild cold, in severe cases meningococcemia develops, characterized by an acute onset of the disease, the appearance of a red rash (does not disappear with pressure), the temperature rises, and confusion is observed.

Danger of illness:

• in severe form, tissue necrosis develops, gangrene of the fingers and extremities, and brain damage are possible. With the development of infectious toxic shock, death occurs quickly.

Tetanus

Tetanus is a dangerous infection that develops in wounds on the skin. The causative agent forms bacterial spores, in the form of which it is located in the external environment. When injected into a wound, it quickly germinates. Therefore, any serious injuries require the prevention of the development of infection - the administration of tetanus toxoid.

Causative agent:

• Tetanus stick.

Typical symptoms:

• tetanus affects the central nervous system, at first it is manifested by tonic tension of the jaw muscles (it is difficult for a person to speak, to open his mouth), later spreads to the whole body, the patient bends over due to muscle hypertonicity, and at the end a respiratory disorder develops.

Danger of illness:

• the main danger is the toxin released by the bacteria, which leads to severe symptoms. As a result of poisoning, tonic tension of all muscles, including the diaphragm and intercostal muscles, occurs, as a result of which a person cannot breathe and dies from hypoxia.

Treatment of bacterial diseases

Any bacterial infection needs planned treatment, because bacteria can cause serious damage to the body. Only the doctor chooses the appropriate therapy regimen, which depends not only on the type of disease, but also on the severity of the course.

Antibiotics

Antibiotics are considered the mainstay of treatment for all infections caused by harmful bacteria. Since the discovery of penicillin in the 1920s, many diseases have been transformed from fatal to curable. The number of complications after operations decreased, and, from which every fourth died, remained dangerous disease only for people at risk.

Modern antibiotics can be divided into two groups:

• Bactericidal - kill pathogenic bacteria.
• Bacteriostatic - slow down growth, stop the reproduction of bacteria.

The former have a more pronounced effect, however, it is the drugs from the second group that are prescribed more often, since, as a rule, they cause fewer complications.

It is also customary to divide drugs according to the spectrum of action:

• Antibiotics wide range actions (penicillins, tetracyclines, macrolides) are used to destroy various types of bacteria. They are effective when treatment needs to be started urgently, even before the tests are carried out. Penicillins are most often prescribed for respiratory bacterial infections.
• Antibiotics that are active against a limited number of bacterial species (often prescribed for tuberculosis and other specific infections).

Any antibiotics must be taken as a course, since if treatment is interrupted, the remaining live bacteria quickly restore the colony population.

Antibiotic problems

Despite the widespread use of antibiotics, doctors today are looking for alternative drugs to treat bacterial infections. This is due to several significant disadvantages of these drugs:

• Development of resistance in bacteria.

Many microorganisms have developed defense mechanisms against drugs, and the use of classical antibiotics is no longer effective. For example, penicillins of the first generation, which actively fought against staphylococci and streptococci, are not used today. Staphylococcus aureus learned to synthesize the enzyme penicillinase, which destroys the antibiotic. Particularly dangerous are new strains of bacteria that have developed drug resistance last generations- the so-called superbugs. The most famous of these is methicillin-resistant Staphylococcus aureus. Also, resistance is rapidly developing Pseudomonas aeruginosa and enterococci.

• The use of broad-spectrum antibiotics leads to dysbiosis.

After such treatment, the balance of microflora is significantly disturbed, complications often develop, the body is weakened not only by the disease, but also by the action of drugs. The use of medications is limited among some population groups: pregnant women, children, patients with liver and kidney damage, and other categories.

Bacteriophages

An alternative to antibiotics can be bacteriophages - viruses that kill a specific class of bacteria. Among the benefits of these drugs:

• Low likelihood of developing resistance, since bacteriophages are organisms that have lived on Earth for several billions of years and continue to infect bacterial cells.
• They do not violate the microflora, since they are specialized drugs - effective only in relation to a specific type of microorganism.
• Can be used by people from risk groups.

Preparations containing bacteriophages are already available in pharmacies today. But still, such therapy loses to antibiotics. Many diseases require immediate treatment, which means that medications of a wide spectrum of action are needed, while bacteriophages are highly specialized - they can be prescribed only after the pathogen has been identified. In addition, the viruses known to date are not capable of destroying such a large list of pathogenic bacteria as antibiotics.

Other treatments

WHO does not recommend the use of antibiotics for all types of bacterial infections. In the event that the microbe does not have high pathogenicity, and the disease proceeds without complications, symptomatic treatment is sufficient - the use of antipyretic, pain relievers, vitamin complexes, heavy drinking and other things. Often the immune system itself can suppress the multiplication of a colony of pathogenic microorganisms. However, in this case, the patient should be under the supervision of a physician who will decide on the appropriateness of a particular method of therapy.

Many deadly bacterial infections have developed effective vaccines... Vaccinations are recommended for the following diseases:

• Tuberculosis.
• Hemophilic infection.
• Pneumococcal infection.
• Diphtheria (toxoid is used - a vaccine that helps to produce antibodies to the bacterial toxin).
• Tetanus (toxoid is used).

Bacteria, nutrition and digestion

Some live bacteria in foods can restore the intestinal microflora, help the digestive tract and get rid of toxins. Others, on the contrary, getting into the digestive tract with food, cause dangerous infections and serious poisoning.

• Pathogenic bacteria often multiply in products that are not stored properly. And the multiplying anaerobic bacteria are especially dangerous here, which easily increase their numbers even in goods in sealed packaging and canned food.
• Another way to contaminate food is through unwashed hands or equipment (knives, cutting boards, etc.). So food poisoning easy to get after street food that is not sanitized.
• Insufficient heat treatment or its absence also increases the likelihood of the multiplication of various disease-causing forms of bacteria.

Medicines with live bacteria

Preparations with beneficial live bacteria are often recommended by nutritionists for various disorders of the gastrointestinal tract. They help with bloating, flatulence, heaviness, poor absorption of food, frequent poisoning.

In the event that the dysbiosis is severely expressed, the doctor may recommend a course of drugs to restore microflora.

• Probiotics are preparations containing live beneficial bacteria.

The medicine is available in capsules with a shell that protects the colonies of microorganisms and helps to deliver them to the intestines in a live form.

• Prebiotics are carbohydrate preparations that contain nutrients for beneficial bacteria.

Such drugs are prescribed if the intestines are inhabited by bifidobacteria and lactobacilli, but their colonies are not large enough.

Lactic acid bacteria are a large group of microorganisms that are able to process glucose with the release of lactic acid. In fact, this means that it is these microbes that are involved in the process of milk fermentation - with their help, all fermented milk products are created. It is thanks to lactic acid bacteria that food does not spoil longer - the acidic environment they create prevents the growth of pathogens. They show the same protective functions in the human intestine.

The main foods that contain lactic acid bacteria are:

• Yogurt without additives.
• Starter cultures, kefir and other fermented milk drinks.
• Acidophilic milk.
• Hard cheeses.
• Sauerkraut.

Major bacteria tables

Disease-causing bacteria

Bacteria in the table are presented by the main types of microbes that can cause disease. However, many of them also include non-pathogenic or opportunistic bacteria.

Name	bacteria	Breath type		Diseases provoked by bacteria
Staphylococci		Facultative anaerobes		Staphylococcus aureus provokes the majority purulent diseases. Including: skin lesions, pneumonia, sepsis. Epidermal staphylococcus aureus causes purulent complications v postoperative period, and saprophytic - cystitis and urethritis (bacteria are found in the urine).
Streptococci		Facultative anaerobes		Scarlet fever, rheumatism (acute rheumatic fever), tonsillitis, pharyngitis, pneumonia, endocarditis, meningitis, abscess.
Clostridia		Anaerobic bacteria		Bacteria can be part of a healthy microflora. At the same time, some species are able to secrete the strongest of the known poisons - the exotoxin botulinum toxin. Clostridia include the causative agents of tetanus, gas gangrene, and botulism.
		Aerobes, facultative anaerobes		Certain types of bacteria cause anthrax and intestinal infections. Escherichia coli also belongs to the genus - a representative of a healthy microflora.
Enterococci		Facultative anaerobes		Urinary tract infections, endocarditis, meningitis, sepsis.

Beneficial bacteria

The bacteria table represents the types of microbes that are vital for humans.

Name	Bacteria shape	Breath type	Benefits for the body
Bifidobacteria		Anaerobes	Human bacteria, which are part of the intestinal and vaginal microflora, help to normalize digestion (drugs with bifidobacteria are prescribed for diarrhea), assimilate vitamins. The peculiarity of bacteria is that they prevent the reproduction of staphylococci, shigella, candida fungus.
	Cocci, sticks	Aerobes requiring a reduced oxygen concentration (microaerophilic bacteria)	A group of bacteria that is united by one characteristic - the ability to induce lactic acid fermentation. They are used in the food industry and are part of probiotics.