Harmful bacteria. Bacteria - general characteristics

How will you react if you find out that in your body the total weight of bacteria is from 1 to 2.5 kilograms?

Most likely, this will cause surprise and shock. Most people believe that bacteria are dangerous and can cause serious harm to the life of the body. Yes, this is true, but there are, in addition to dangerous, also beneficial bacteria, moreover, vital for human health.

They exist within us, taking a huge part in various metabolic processes. Actively participate in the proper functioning of life processes, both in the internal and external environment of our body. These bacteria include bifidobacteria. Rhizobium and E. coli, and many more.

Beneficial bacteria for humans
The human body has millions of all kinds of beneficial bacteria that take part in various functions of our body. As you know, the number of bacteria in the body ranges from 1 to 2.5 kilograms, this volume contains a huge number of different bacteria. These bacteria can be present in all accessible parts of the body, but they are mostly found in the intestines where they aid in the digestive process. They also play a very important role in helping to prevent bacterial infections of the genital parts of the body, as well as yeast (fungal) infections.

Some beneficial bacteria for humans are acid-base balance regulators and are involved in maintaining pH. Some are even involved in protecting the skin (barrier function) from many infections. They are necessary and useful both as active workers in the production of vitamin K, and in the role of the normal functioning of the immune system.

Environment and beneficial bacteria
The name of one of the most beneficial bacteria in the environment is Rhizobium. These bacteria are also called nitrogen-fixing bacteria. They are present in the root nodules of plants, and release nitrogen into the atmosphere. Considered to be very beneficial to the environment.

Other equally important jobs that bacteria do for the environment are related to the digestion of organic waste, which helps maintain soil fertility. Azotobacters are a group of bacteria that are involved in the conversion of nitrogen gas into nitrates, which are used further down the chain by Rhizobium - nitrogen-fixing microbes.

Other Functions of Beneficial Bacteria
Bacteria are beneficial by participating in fermentation processes. Therefore, in many industries that are associated with the production of beer, wine, yoghurts and cheeses, they cannot do without the use of these microorganisms for fermentation processes. The bacteria used in fermentation processes are called Lactobacillus.

Bacteria play an important role in waste water treatment. They are used to convert organic matter into methane. Hence, they are applied in many industries. Some bacteria are also useful in cleaning up oil spills on the surface of the Earth's water basins.

Other bacteria are used in the production of antibiotics such as tetracycline and streptomycin. Streptomyces are soil bacteria used in the industrial production of antibiotics in the pharmaceutical industry.

E.coli, - bacteria that are present in the stomach of animals, such as cows, buffaloes, etc. help them in the digestion of plant foods.

Along with these beneficial bacteria, there are some dangerous and harmful bacteria that can lead to infections, but they are few in number.

A person often treats his body relatively lightly. Yes, many people know where the heart, kidneys, intestines, etc. are located. Some have a deeper knowledge of the structure of the human body. But few people dare to look at themselves not only as a person, but as a biological mechanism that works according to certain laws and lives its own complex and multidimensional biological life. So, for example, not everyone clearly understands how valuable our biological cohabitation with protozoa is and how terrible the bacterial threat is.

Bacteria without which a person cannot survive

The human body is inhabited by a huge number of bacteria, without which a person cannot survive. The total weight is from 1.5 to 2.5 kg. Such a useful stable symbiosis was formed:

in the gastrointestinal tract;
on the skin;
in the nasopharynx and oral cavity.

The main principle of the work of bacteria in the body is the creation of such an environment on the tissues of organs in which harmful microbes cannot survive. Accordingly, getting on the skin, in the nasopharynx or in the gastrointestinal tract, pathogenic microbes simply die, since the environment already formed by beneficial microbes on the tissues of these organs is fatal for virulent (dangerous) prokaryotes.

This is a general picture of the influence of beneficial bacteria, while the local effect of microbes has features depending on the organ in which such a symbiotic interaction occurs.

Gastrointestinal tract

The bacteria that inhabit the human gastrointestinal tract perform several functions at once, thanks to which a person has the opportunity to survive as a biological organism:

Microbes create an antagonistic environment for pathogenic microbes in the intestine. This role of beneficial microorganisms boils down to the fact that they create an acidic environment in the intestines, and pathogenic microbes do not live well in an acidic environment.
The same beneficial bacteria digest plant foods that enter the intestines. Enzymes synthesized by the human body are not able to digest plant cells containing cellulose, and bacteria feed on such cells freely, thus playing another important role.
Also, beneficial bacteria synthesize vitamins of groups B and K that are necessary for a person. The role of vitamins of group K is to ensure metabolism in bones and connective tissues. The role of B vitamins is global. These low molecular weight organic compounds are involved in a huge number of processes, from the release of energy from carbohydrates to the synthesis of antibodies and the regulation of the nervous system. Despite the fact that B vitamins are present in many products, it is thanks to their synthesis by the intestinal microflora that the body receives the amount of these vitamins that is necessary for normal human life.

The main part of the beneficial intestinal microflora is lactic acid bacteria. Despite the fact that these bacteria may have different names, they have the same type of effect on the body. Lactic acid bacteria ferment natural sugars, resulting in the formation of a product such as lactic acid.

The most popular lactic acid microorganisms today are those that are advertised as the main probiotic agent in the composition of healthy products.

bifidobacteria- filamentous lactic acid microorganisms that cover the surface of the intestine and prevent harmful microbes from gaining a foothold and multiplying on its walls. The total weight of lactic acid bifidobacteria in relation to other symbiont bacteria is about 80%.
lactobacilli- gram-positive lactic acid rods, the main role of which is not only the digestion of plant foods and the creation of an antagonistic environment, but also the stimulation of antibody synthesis. These are microorganisms that have a huge impact on the human immune system.

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In addition to useful lactic acid prokaryotes, there are conditionally harmful ones in the gastrointestinal tract -. Despite the fact that they can also have a beneficial effect, for example, the bacteria of the Escherichia coli group also synthesize vitamins of the K group, with an increase in their number in the gastrointestinal tract, the effect becomes harmful: E. coli poison the body with toxins.

The total weight of E. coli that are present in the human body is very small compared to two kilograms of beneficial microorganisms.

Bacteria on the skin, in the mouth and in the nasopharynx

Microorganisms that inhabit the human skin play the role of a natural biological shield, they also do not allow harmful bacteria to develop active activity on the skin and thereby have a toxic effect on the entire body.

The main bacteria that control the safety of the skin, mouth and nasopharynx are:

micrococci;
streptococci;
staphylococci.

Streptococci and staphylococci have harmful (pathogenic) representatives in their genus that can poison the body.

Causes of diseases

A logical question arises: if a person is protected from all sides by a biological shield, then why do people still get sick, why does this shield not work?

The body's resistance to pathogenic agents largely depends on the immune system. Therefore, it is important how much work is done to ensure that the immune system is sufficiently active.

The second important circumstance is the characteristics of the most harmful agent and how it affects the body.

So, for a long time, typhus was a deadly threat to humans.

Typhus is the collective name for several deadly diseases that have claimed many lives until cures were found.

Common features characteristic of all types of typhus:

a person quickly loses weight;
against the background of intoxication and weight loss, a severe fever begins;
all of these painful manifestations cause severe nervous breakdown and the person dies.

Despite the common symptoms, the causes of typhoid fever are different each time.

Disease causing bacteria

In the intestines of lice, a large number of rickettsiae. However, the likelihood of infection does not depend on how many lice are in close proximity to a person, but on how actively a person begins to fight lice. Scratching lice on oneself is the main cause of infection with typhus. It is from the crushed intestines of the louse that the rickettsia enter the wounds on the skin and further into the human bloodstream.

The main symptoms of typhus:

fever (body temperature above 40ºС);
backache;
pink rash in the abdomen;
the patient's consciousness is inhibited almost to the point of coma.

The treatment of typhus, like the treatment of any bacterial infection, is based on antibiotics. Antibiotics of the tetracycline group are used to treat this type of typhoid.

Another terrible type of typhus - returnable. It is carried by ticks and lice. But it is the spirochete Borrelia bacteria that are the causative agents. Infection occurs during a tick bite.

The main symptoms of infection:

vomit;
the spleen and liver are enlarged;
begins a mental disorder and hallucinations.

The same symptoms occur if the carriers were lice.

Treatment - antibiotics of the penicillin and chloramphenicol groups, as well as arsenic preparations.

Typhoid fever. The causative agent is a pathogenic bacterial bacillus from the genus Salmonella. This type of typhoid is dangerous only for humans, animals do not get sick with typhoid fever. Pathogens enter the stomach with food. Main symptoms:

the appearance of bacteria in the urine (bacteremia);
general symptoms of intoxication (pallor, headache, heart rhythm disorder);
bloated belly;
delusions, hallucinations and other mental disorders.

Treatment is also carried out with antibiotics of the chloramphenicol and penicillin groups and is accompanied by general strengthening therapy.

In addition to typhoid pathogens, a person is threatened by a host of other pathogenic microbes, the timely detection of which, as well as the identification of infection symptoms, its identification and treatment, can cost a person life.

The same plague is a disease with a high lethality, the cause of which is a plague bacillus. Symptoms are weight loss, fever and dehydration. A person dies from dehydration.

The carriers of the plague bacillus can be rodents, pets, insects.

Plague is treated with antibiotics of the streptomycin group. An important role is played by prevention and general strengthening of the body.

Science and life // Illustrations

Staphylococcus aureus.

Spirilla.

Trypanosoma.

Rotaviruses.

Rickettsia.

Yersinia.

Leishmania.

Salmonella.

Legionella.

Even 3,000 years ago, the great Greek Hippocrates guessed that contagious diseases are caused and carried by living beings. He called them miasma. But the human eye could not distinguish them. At the end of the 17th century, the Dutchman A. Leeuwenhoek created a sufficiently powerful microscope, and only then was it possible to describe and draw a variety of forms of bacteria - single-celled organisms, many of which are the causative agents of various human infectious diseases. Bacteria is one of the types of microbes (“microbe” - from the Greek “micros” - small and “bios” - life), however, the most numerous.

After the discovery of microbes and the study of their role in human life, it turned out that the world of these smallest organisms is very diverse and requires a certain systematization and classification. And today, experts use a system according to which the first word in the name of a microorganism means the genus, and the second - the species name of the microbe. These names (usually Latin or Greek) are "speaking". Thus, the name of some microorganisms reflects some of the most striking features of their structure, in particular, the form. This group primarily includes bacteria. In form, all bacteria are divided into spherical - cocci, rod-shaped - actually bacteria and convoluted - spirilla and vibrios.

globular bacteria- pathogenic cocci (from the Greek "coccus" - grain, berry), microorganisms that differ from each other in the location of cells after their division.

The most common of them are:

- staphylococci(from the Greek "stafile" - a bunch of grapes and "kokkus" - a grain, a berry), which received such a name because of the characteristic shape - a cluster resembling a bunch of grapes. The type of these bacteria has the most pathogenic effect. staphylococcus aureus(“Staphylococcus aureus”, as it forms clusters of golden color), causing various purulent diseases and food intoxications;

- streptococci(from the Greek "streptos" - a chain), whose cells after division do not diverge, but form a chain. These bacteria are the causative agents of various inflammatory diseases (tonsillitis, bronchopneumonia, otitis media, endocarditis, and others).

rod-shaped bacteria, or rods,- these are microorganisms of a cylindrical shape (from the Greek "bacterion" - a stick). From their name came the name of all such microorganisms. But those bacteria that form spores (a protective layer that protects against adverse environmental influences) are called bacilli(from the Latin "bacillum" - a stick). The spore-forming rods include the anthrax bacillus, a terrible disease known since ancient times.

The twisted shapes of bacteria are spirals. For example, spirilla(from Latin "spira" - bend) are bacteria that have the form of spirally curved rods with two or three curls. These are harmless microbes, with the exception of the causative agent of "rat bite disease" (Sudoku) in humans.

A peculiar form is also reflected in the name of microorganisms belonging to the family spirochete(from Latin "spira" - bend and "hate" - mane). For example, members of the family leptospira are distinguished by an unusual shape in the form of a thin thread with small, closely spaced curls, which makes them look like a thin twisted spiral. And the very name "leptospira" is translated as such - "narrow spiral" or "narrow curl" (from the Greek "leptos" - narrow and "spera" - gyrus, curl).

corynebacteria(causative agents of diphtheria and listeriosis) have characteristic club-shaped thickenings at the ends, as indicated by the name of these microorganisms: from lat. "korine" - a mace.

Today all known viruses also grouped into genera and families, including on the basis of their structure. Viruses are so small that in order to see them through a microscope, it must be much stronger than a conventional optical one. An electron microscope magnifies hundreds of thousands of times. Rotaviruses got its name from the Latin word "rota" - a wheel, since virus particles under an electron microscope look like small wheels with a thick sleeve, short spokes and a thin rim.

And the name of the family coronaviruses due to the presence of villi, which are attached to the virion through a narrow stem and expand towards the distant end, resembling the solar corona during an eclipse.

The name of some microorganisms is associated with the name of the organ they infect or the disease they cause. For example, title "meningococci" It is formed from two Greek words: “meningos” - the meninges, since these microbes mainly affect it, and “coccus” - a grain, indicating that they belong to spherical bacteria - cocci. The name is derived from the Greek word "pneumon" (lung). "pneumococci" These bacteria cause lung disease. Rhinoviruses- causative agents of a contagious rhinitis, hence the name (from the Greek "rhinos" - nose).

The origin of the name of a number of microorganisms is also due to their other most characteristic features. So, a distinctive feature of vibrios - bacteria in the form of a short curved rod - the ability to rapid oscillatory movements. Their name is derived from the French word vibrator- vibrate, vibrate, vibrate. Among the vibrios, the causative agent of cholera, which is called "cholera vibrio", is the most famous.

Bacteria of the genus proteus(Proteus) refer to the so-called microbes that are dangerous for some, but not for others. In this regard, they were named after the sea deity from ancient Greek mythology - Proteus, who was credited with the ability to arbitrarily change his appearance.

Monuments are erected to great scientists. But sometimes the names of microorganisms discovered by them also become monuments. For example, microorganisms that occupy an intermediate position between viruses and bacteria have been named "rickettsia" in honor of the American explorer Howard Taylor Ricketts (1871-1910), who died of typhus while studying the causative agent of this disease.

The causative agents of dysentery were thoroughly studied by the Japanese scientist K. Shiga in 1898, in his honor they subsequently received their generic name - "shigella".

Brucella(causative agents of brucellosis) are named after the English military doctor D. Bruce, who in 1886 for the first time managed to isolate these bacteria.

Bacteria grouped in a genus "yersinia", named after the famous Swiss scientist A. Yersin, who discovered, in particular, the causative agent of the plague - Yersinia pestis.

By the name of the English doctor V. Leishman, the simplest unicellular organisms (causative agents of leishmaniasis) are named leishmania, described in detail in 1903.

The generic name is associated with the name of the American pathologist D. Salmon "salmonella", a rod-shaped intestinal bacterium that causes diseases such as salmonellosis and typhoid fever.

And the German scientist T. Escherich owe their name Escherichia- Escherichia coli, first isolated and described by him in 1886.

In the origin of the name of some microorganisms, a certain role was played by the circumstances under which they were discovered. For example, generic name "legionella" appeared after an outbreak in 1976 in Philadelphia among the delegates of the convention of the American Legion (an organization that unites US citizens - participants in international wars) of a severe respiratory disease caused by these bacteria - they were transmitted through the air conditioner. BUT coxsackie viruses were first isolated from children with polio in 1948 in the village of Coxsackie (USA), hence the name.

Rice. 1. The human body is 90% microbial cells. It contains from 500 to 1000 different types of bacteria or trillions of these amazing residents, which is up to 4 kg of total weight.

Rice. 2. Bacteria inhabiting the oral cavity: Streptococcus mutants (green). Bacteroides gingivalis, causes periodontitis (purple). Candida albicus (yellow). Causes candidiasis of the skin and internal organs.

Rice. 7. Mycobacterium tuberculosis. Bacteria have been causing disease in humans and animals for thousands of years. Tuberculosis bacillus is extremely stable in the external environment. In 95% of cases, it is transmitted by airborne droplets. Most often affects the lungs.

Rice. 8. The causative agent of diphtheria is Corynebacterium or Leffler's bacillus. More often it develops in the epithelium of the mucous layer of the tonsils, less often in the larynx. Swelling of the larynx and enlarged lymph nodes can lead to asphyxia. The pathogen toxin is fixed on the membranes of the cells of the heart muscle, kidneys, adrenal glands and nerve ganglia and destroys them.

Rice. 9. Causative agents of staphylococcal infection. Pathogenic staphylococci cause extensive lesions of the skin and its appendages, lesions of many internal organs, food poisoning, enteritis and colitis, sepsis and toxic shock.

Rice. 10. Meningococci are the causative agents of meningococcal infection. Up to 80% of patients are children. The infection is transmitted by airborne droplets from sick and healthy carriers of the bacteria.

Rice. 11. Whooping cough bordetella.

Rice. 12. The causative agents of scarlet fever are streptococci pyogenes.

Harmful bacteria of water microflora

The habitat of many microbes is water. Up to 1 million microbial bodies can be counted in 1 cm3 of water. Pathogenic microorganisms enter the water from industrial enterprises, settlements and livestock farms. Water with pathogenic microbes can become a source dysentery, cholera, typhoid fever, tularemia, leptospirosis, etc. Vibrio cholerae and can stay in the water for a long time.

Rice. 13. Shigella. The pathogens cause bacillary dysentery. Shigella destroy the mucosal epithelium of the colon, causing severe ulcerative colitis. Their toxins affect the myocardium, nervous and vascular systems.

Rice. fourteen. . Vibrios do not destroy the cells of the mucous layer of the small intestine, but are located on their surface. The toxin cholerogen is released, the action of which leads to a violation of water-salt metabolism, in connection with which the body loses up to 30 liters of fluid per day.

Rice. 15. Salmonella - causative agents of typhoid and paratyphoid. The epithelium and lymphoid elements of the small intestine are affected. With the blood flow, they enter the bone marrow, spleen and gallbladder, from which pathogens again enter the small intestine. As a result of immune inflammation, the wall of the small intestine ruptures and peritonitis occurs.

Rice. 16. Causative agents of tularemia (blue coccobacteria). Affects the respiratory and intestines. They have the peculiarity of penetrating into the human body through intact skin and mucous membranes of the eyes, nasopharynx, larynx and intestines. A feature of the disease is the defeat of the lymph nodes (primary bubo).

Rice. 17. Leptospira. Affect the human capillary network, often the liver, kidneys and muscles. The disease is called infectious jaundice.

Harmful bacteria of soil microflora

Billions of "bad" bacteria live in the soil. In the 30 cm thickness of 1 hectare of land there are up to 30 tons of bacteria. Possessing a powerful set of enzymes, they are engaged in the breakdown of proteins to amino acids, thereby taking an active part in the processes of decay. However, these bacteria bring a lot of trouble to a person. Thanks to the activity of these microbes, food spoils very quickly. Man has learned to protect long-term storage products by sterilization, salting, smoking and freezing. Some types of these bacteria can spoil even salted and frozen foods. get into the soil from sick animals and humans. Some types of bacteria and fungi stay in the soil for decades. This is facilitated by the peculiarity of these microorganisms to form spores, which for many years protect them from adverse environmental conditions. They cause the most terrible diseases - anthrax, botulism, and tetanus.

Rice. 18. The causative agent of anthrax. For decades, it remains in the soil in a spore-like state. A particularly dangerous disease. Its second name is malignant carbuncle. The prognosis of the disease is unfavorable.

Rice. 19. The causative agent of botulism releases the strongest toxin. 1 mcg of this poison kills a person. Botulinum toxin affects the nervous system, oculomotor nerves, up to paralysis and cranial nerves. Mortality from botulism reaches 60%.

Rice. 20. The causative agents of gas gangrene multiply very quickly in the soft tissues of the body without air access, causing severe lesions. In a spore-like state, it remains in the external environment for a long time.

Rice. 21. Putrefactive bacteria.

Rice. 22. Defeat by putrefactive bacteria of food.

Harmful bacteria infecting wood

A number of bacteria and fungi intensively decompose fiber, playing an important sanitary role. However, among them there are bacteria that cause severe diseases in animals. Molds destroy wood. wood stain mushrooms paint wood in different colors. house mushroom causes wood to decay. As a result of the vital activity of this fungus, wooden buildings are destroyed. Great damage is caused by the activity of these fungi in the destruction of livestock buildings.

Rice. 23. The photo shows how the house fungus destroyed the wooden floor beams.

Rice. 24. Spoiled appearance of logs (blue) affected by a wood-staining fungus.

Rice. 25. House mushroom Merulius Lacrimans. a - cotton-like mycelium; b - young fruiting body; c - old fruiting body; d - old mycelium, cords and rotten wood.

Harmful bacteria in food

Products contaminated with dangerous bacteria become a source of intestinal diseases: typhoid, salmonellosis, cholera, dysentery etc. Toxins that emit staphylococci and botulinum bacterium cause toxic infections. Cheese and all dairy products may be affected butyric bacteria, which cause butyric fermentation, as a result of which the products have an unpleasant odor and color. vinegar sticks cause acetic fermentation, which leads to souring of wine and beer. Bacteria and micrococci that cause putrefaction contain proteolytic enzymes that break down proteins, which give the products a foul-smelling odor and a bitter taste. Mold covers products as a result of damage fungi.

Rice. 26. Bread affected by mold.

Rice. 27. Cheese affected by mold and putrefactive bacteria.

Rice. 28. "Wild yeast" Pichia pastoris. Photo taken at 600x magnification. A vicious pest of beer. Found ubiquitously in nature.

Harmful bacteria that break down dietary fats

Butyric microbes are everywhere. 25 of their species cause butyric fermentation. vital activity fat-splitting bacteria leads to rancidity of the oil. Under their influence, soybean and sunflower seeds go rancid. Butyric fermentation, which these microbes cause, spoils the silage, and it is poorly eaten by livestock. And wet grain and hay, affected by butyric microbes, warms itself. The moisture contained in butter is a good breeding ground. putrefactive bacteria and yeasts. Because of this, the oil deteriorates not only outside, but also inside. If the oil is stored for a long time, then fungi.

Rice. 29. Caviar oil affected by fat-splitting bacteria.

Harmful bacteria affecting eggs and egg products

Bacteria and fungi penetrate the eggs through the pores of the outer shell and damage it. Most often, eggs are infected with salmonella bacteria and mold fungi, egg powder - salmonella and.

Rice. 30. Spoiled eggs.

Harmful bacteria in canned food

for humans are toxins botulinum sticks and perfringens sticks. Their spores exhibit high thermal stability, which allows microbes to survive after pasteurization of canned food. Being inside the jar, without access to oxygen, they begin to multiply. At the same time, carbon dioxide and hydrogen are released, from which the can swells. Eating such a product causes severe food toxicosis, which is characterized by an extremely severe course and often ends in the death of the patient. Canned meat and vegetables are amazing acetic acid bacteria as a result of which the contents of the canned food sour. Development does not cause swelling of canned food, since staphylococcus aureus does not produce gases.

Rice. 31. Canned meat affected by acetic acid bacteria, as a result of which the contents of the canned food become sour.

Rice. 32. Bloated canned food may contain botulinum rods and perfringens rods. It inflates the jar with carbon dioxide, which is released by bacteria during reproduction.

Harmful bacteria in grain products and bread

Ergot and other molds that infect grains are the most dangerous to humans. The toxins from these mushrooms are heat stable and are not destroyed by baking. Toxicosis caused by the use of such products is difficult. Flour afflicted lactic acid bacteria, has an unpleasant taste and a specific smell, lumpy in appearance. Already baked bread is affected bacillus subtilis(Vas. subtilis) or "stringing disease". Bacilli secrete enzymes that break down bread starch, which is manifested, at first, by an odor not characteristic of bread, and then by the stickiness and ductility of the bread crumb. Green, white and capitate mold hit already baked bread. It spreads through the air.

Rice. 33. In the photo, the ergot is purple. Low doses of ergot cause severe pain, mental disturbance, and aggressive behavior. High doses of ergot cause painful death. Its action is associated with muscle contraction under the influence of alkaloids of the fungus.

Rice. 34. Mushroom fungus.

Rice. 35. Spores of green, white and capitate mold can get from the air on already baked bread and infect it.

Harmful bacteria that affects fruits, vegetables and berries

Fruits, vegetables and berries seed soil bacteria, fungi and yeast, which cause intestinal infections. Mycotoxin patulin, which is secreted mushrooms of the genus Penicillium capable of causing cancer in humans. Yersinia enterocolitica causes the disease yersiniosis or pseudotuberculosis, which affects the skin, gastrointestinal tract and other organs and systems.

Rice. 36. Defeat of berries by mold fungi.

Rice. 37. Skin lesions in yersiniosis.

Harmful bacteria enter the human body with food, through air, wounds and mucous membranes. The severity of diseases caused by pathogenic microbes depends on the poisons they produce and the toxins that occur during their mass death. Over the millennia, they have acquired many devices that allow them to penetrate and stay in the tissues of a living organism and resist immunity.

To study the harmful effects of microorganisms on the body and to develop preventive measures - this is the task of man!

Articles in the section "What do we know about microbes"Most popular

The totality of bacteria that inhabit the human body has a common name - the microbiota. In a normal, healthy human microflora, there are several million bacteria. Each of them plays an important role for the normal functioning of the human body.

In the absence of any type of beneficial bacteria, a person begins to get sick, the work of the gastrointestinal tract and respiratory tract is disrupted. Beneficial bacteria for humans are concentrated on the skin, in the intestines, on the mucous membranes of the body. The number of microorganisms is regulated by the immune system.

Normally, the human body contains both beneficial and pathogenic microflora. Bacteria can be beneficial or pathogenic.

There are many more beneficial bacteria. They make up 99% of the total number of microorganisms.

In this position, the necessary balance is maintained.

Among the different types of bacteria that live on the human body, we can distinguish:

bifidobacteria;
lactobacilli;
enterococci;
coli.

bifidobacteria

This type of microorganisms is the most common, involved in the production of lactic acid and acetate. It creates an acidic environment, thereby neutralizing most pathogenic microbes. Pathogenic flora ceases to develop and cause the processes of decay and fermentation.

Bifidobacteria play an important role in the life of a child, since they are responsible for the presence of an allergic reaction to any food. In addition, they have an antioxidant effect, prevent the development of tumors.

The synthesis of vitamin C is not complete without the participation of bifidobacteria. In addition, there is information that bifidobacteria help to absorb vitamins D and B, which are necessary for a person for normal life. In the presence of a deficiency of bifidobacteria, even taking synthetic vitamins of this group will not bring any result.

lactobacilli

This group of microorganisms is also important for human health. Due to their interaction with other inhabitants of the intestine, the growth and development of pathogenic microorganisms is blocked, pathogens of intestinal infections are suppressed.

Lactobacilli are involved in the formation of lactic acid, lysocin, bacteriocins. This is a great help to the immune system. If there is a deficiency of these bacteria in the intestine, then dysbacteriosis develops very quickly.

Lactobacilli colonize not only the intestines, but also the mucous membranes. So these microorganisms are important for women's health. They maintain the acidity of the vaginal environment and prevent development.

coli

Not all types of E. coli are pathogenic. Most of them, on the contrary, perform a protective function. The usefulness of the genus lies in the synthesis of cocilin, which actively resists the bulk of pathogenic microflora.

These bacteria are useful for the synthesis of various groups of vitamins, folic and nicotinic acid. Their role in health should not be underestimated. For example, folic acid is essential for the production of red blood cells and the maintenance of normal hemoglobin levels.

Enterococci

They help digest sucrose. Living mainly in the small intestine, they, like other beneficial non-pathogenic bacteria, provide protection against excessive reproduction of harmful elements. At the same time, enterococci are conditionally safe bacteria.

If they begin to exceed the permissible norms, various bacterial diseases develop. The list of diseases is very large. Ranging from intestinal infections, ending with meningococcal.

The positive effect of bacteria on the body

The beneficial properties of non-pathogenic bacteria are very diverse. As long as there is a balance between the inhabitants of the intestines and mucous membranes, the human body functions normally.

Most bacteria are involved in the synthesis and breakdown of vitamins. Without their presence, B vitamins are not absorbed by the intestines, which leads to disorders of the nervous system, skin diseases, and a decrease in hemoglobin.

The bulk of undigested food components that have reached the large intestine are broken down precisely due to bacteria. In addition, microorganisms ensure the constancy of water-salt metabolism. More than half of the entire microflora is involved in the regulation of the absorption of fatty acids and hormones.

The intestinal microflora forms local immunity. It is here that the destruction of the bulk of pathogenic organisms takes place, the harmful microbe is blocked.

Accordingly, people do not feel bloating and flatulence. An increase in lymphocytes provokes active phagocytes to fight the enemy, stimulate the production of immunoglobulin A.

Useful non-pathogenic microorganisms have a positive effect on the walls of the small and large intestines. They maintain a constant level of acidity there, stimulate the lymphoid apparatus, the epithelium becomes resistant to various carcinogens.

Intestinal peristalsis also largely depends on what microorganisms are in it. Suppression of the processes of decay and fermentation is one of the main tasks of bifidobacteria. Many microorganisms for many years develop in symbiosis with pathogenic bacteria, thereby controlling them.

Biochemical reactions that constantly occur with bacteria release a lot of heat energy, maintaining the overall heat balance of the body. Microorganisms feed on undigested residues.

Dysbacteriosis

Dysbacteriosis is a change in the quantitative and qualitative composition of bacteria in the human body . In this case, beneficial organisms die, and harmful organisms actively multiply.

Dysbacteriosis affects not only the intestines, but also mucous membranes (there may be dysbacteriosis of the oral cavity, vagina). In the analyzes, the names will prevail: streptococcus, staphylococcus, micrococcus.

In the normal state, beneficial bacteria regulate the development of pathogenic microflora. Skin, respiratory organs are usually under reliable protection. When the balance is disturbed, a person feels the following symptoms: intestinal flatulence, bloating, abdominal pain, upset.

Later, weight loss, anemia, vitamin deficiency may begin. From the reproductive system, abundant discharge is observed, often accompanied by an unpleasant odor. Irritations, roughness, cracks appear on the skin. Dysbacteriosis is a side effect after taking antibiotics.

If you find such symptoms, you should definitely consult a doctor who will prescribe a set of measures to restore normal microflora. This often requires taking probiotics.