What are the names of the types of bacteria? Harmful and beneficial bacteria

The most ancient living organism on our planet. Not only have its members survived for billions of years, but they are also powerful enough to wipe out every other species on Earth. In this article we will look at what types of bacteria there are.

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

Discovery of bacteria

Let's begin our excursion into the kingdom of microorganisms with a definition. What does "bacteria" mean?

The term comes from the ancient Greek word for "stick". Christian Ehrenberg introduced it into the academic lexicon. These are nuclear-free microorganisms that do not have a nucleus. Previously, they were also called “prokaryotes” (nuclear-free). But in 1970 there was a division into archaea and eubacteria. However, this concept is still more often used to mean all prokaryotes.

The science of bacteriology studies what types of bacteria there are. Scientists say that given time about ten thousand open various types these living beings. However, it is believed that there are more than a million varieties.

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

After Nehemiah Grew confirmed the information, Leeuwenhoek became a world-famous scientist, a discoverer. But in his notes he called them “animalcules.”

Ehrenberg continued his work. It was this researcher who coined the modern term “bacteria” in 1828.

Microorganisms are also used for military purposes. With the help of various species, a deadly substance is created. For this, not only the bacteria themselves are used, but also the toxins released by them.

In a peaceful way, science uses single-celled organisms for research in the fields of genetics, biochemistry, genetic engineering and molecular biology. With the help of successful experiments, algorithms for the synthesis of vitamins, proteins and other necessary for a person substances.

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. According to researchers, there is about one kilogram of these microorganisms inside the body!

In everyday life, we encounter pathogenic bacteria everywhere. According to statistics, the largest number of colonies are found on the handles of supermarket trolleys, followed by computer mice in Internet cafes, and only in third place are the handles of public restrooms.

Beneficial bacteria

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

Half a century ago, no one even thought about such an issue as the state of microflora in the intestines. Everything was OK. Eating more natural and healthier, less hormones and antibiotics, less chemical emissions into the environment.

Today, in conditions of poor nutrition, stress, and an overabundance of antibiotics, dysbiosis and related problems are taking 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 issues as food allergies, lactose intolerance, gastrointestinal disorders and other ailments.

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

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

The first two are designed to stimulate the immune system, as well as reduce the growth of some 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 types of bacteria there are. The types and names of the most common beneficial microorganisms were announced above. Next we will talk about the “single-cell enemies” of humans.

There are some that are harmful only to humans, while others are deadly for animals or plants. People have learned to use the latter, in particular, to destroy weeds and annoying insects.

Before delving into what types there 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 food, by 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 to several million bacteria within just a few hours.

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

Preventive measures to prevent the disease are of three types. These are vaccinations and vaccinations, interruption of transmission routes (gauze bandages, 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'll talk about what bacteria are in urine a little later. Now it is worthwhile to dwell separately on where, in fact, single-celled creatures appear there.

Ideally, a person's urine is sterile. There cannot be any foreign organisms there. The only way bacteria can enter waste is at the site where waste is removed 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 when the indicator increases 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 types of bacteria are in bladder, is completely incorrect. Microorganisms do not enter the discharge from this organ. Scientists today have identified several reasons leading to the presence of single-celled creatures in urine.

• Firstly, this is promiscuous sex life.
• Secondly, diseases of the genitourinary system.
• Thirdly, neglect of personal hygiene rules.
• Fourthly, 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 are found only in cases of disease. We promised to tell you what bacteria are. The names will be given only of those species that are most often found in the analysis results.

So, let's begin. Lactobacillus is a representative of anaerobic organisms, a gram-positive bacterium. She must be in digestive system person. Its presence in the urine indicates some malfunctions. Such an event is not critical, but it is an unpleasant wake-up call that you should take serious care of yourself.

Proteus is also a natural inhabitant of the gastrointestinal tract. But its presence in the urine indicates a failure in the excretion of feces. This microorganism passes from food into urine only in this way. A sign of the presence of a large amount of proteus in the waste is a burning sensation in the lower abdomen and painful urination when the liquid is dark in color.

Enterococcus fecalis is very similar to the previous bacterium. It gets into the urine the same way, multiplies quickly and is difficult to treat. In addition, enterococcus microorganisms are resistant to most antibiotics.

Thus, in this article we have 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.

The human intestine is home to microorganisms that make up a total mass of up to two kilograms. They form the local flora. The ratio is strictly maintained on the principle of expediency.

Bacterial contents are heterogeneous in function and significance for the host organism: some bacteria in all conditions provide support through the proper functioning of the intestines, and therefore are called beneficial. Others are only waiting for the slightest disruption in control and weakening of the body in order to turn into a source of infection. They are called opportunistic.

The introduction of foreign bacteria into the intestines that can cause disease is accompanied by a violation of the optimal balance, even if the person is not sick, but is a carrier of the infection.

Treatment of the disease with medications, especially antibacterial ones, has a detrimental effect not only on the causative agents of the disease, but also on beneficial bacteria. The problem arises of how to eliminate the consequences of therapy. Therefore, scientists created large group new drugs that supply live bacteria to the intestines.

What bacteria form the intestinal flora?

About five thousand species of microorganisms live in the human digestive tract. They perform the following functions:

• They help with their enzymes to break down substances found in foods until they are properly digested and absorbed through the intestinal wall into the bloodstream;
• destroy unnecessary residues of food digestion, toxins, toxic substances, gases in order to prevent rotting processes;
• produce special enzymes for the body, biologically active substances (biotin), vitamin K and folic acid, which are necessary for life;
• participate in the synthesis of immune components.

Studies have shown that some bacteria (bifidobacteria) protect the body from cancer.

Probiotics gradually displace pathogenic microbes, depriving them of nutrition and directing immune cells to them

The main beneficial microorganisms include: bifidobacteria (comprising 95% of the total flora), lactobacilli (almost 5% by weight), Escherichia. The following are considered opportunistic:

• staphylococci and enterococci;
• mushrooms of the genus Candida;
• clostridia.

They become dangerous when a person’s immunity declines and the acid-base balance in the body changes. Examples of harmful or pathogenic microorganisms are Shigella and Salmonella - the causative agents of typhoid fever and dysentery.

Beneficial live bacteria for the intestines are also called probiotics. So, they began to call specially created substitutes for normal intestinal flora. Another name is eubiotics.
Now they are effectively used to treat digestive pathologies and the consequences of the negative effects of drugs.

Types of probiotics

Preparations with live bacteria were gradually improved and updated in properties and composition. In pharmacology, they are usually divided into generations. The first generation includes drugs containing only one strain of microorganisms: Lactobacterin, Bifidumbacterin, Colibacterin.

The second generation is formed by antagonist drugs containing unusual flora that can resist pathogenic bacteria and support digestion: Bactistatin, Sporobacterin, Biosporin.

The third generation includes multicomponent drugs. They contain several strains of bacteria with bioadditives. The group includes: Linex, Atsilakt, Acipol, Bifiliz, Bifiform. The fourth generation consists only of preparations from bifidobacteria: Florin Forte, Bifidumbacterin Forte, Probifor.

Based on their bacterial composition, probiotics can be divided into those containing as the main component:

• bifidobacteria - Bifidumbacterin (forte or powder), Bifiliz, Bifikol, Bifiform, Probifor, Biovestin, Lifepack Probiotics;
• lactobacilli - Linex, Lactobacterin, Atsilakt, Acipol, Biobakton, Lebenin, Gastrofarm;
• colibacteria - Colibacterin, Bioflor, Bifikol;
• enterococci - Linex, Bifiform, dietary supplements domestic production;
• yeast-like fungi - Biosporin, Bactisporin, Enterol, Baktisubtil, Sporobacterin.

What should you consider when purchasing probiotics?

Pharmacological companies in Russia and abroad can produce identical analogue drugs under different names. Imported ones are, of course, much more expensive. Studies have shown that people living in Russia are more adapted to local strains of bacteria.

It’s still better to buy your own drugs

Another negative is that, as it turned out, imported probiotics contain only a fifth of the declared volume of living microorganisms and do not settle in the intestines of patients for a long time. Before purchasing, consultation with a specialist is required. This is caused by serious complications from improper use of drugs. Patients registered:

• exacerbation of cholelithiasis and urolithiasis;
• obesity;
• allergic reactions.

Live bacteria should not be confused with prebiotics. These are also medicines, but do not contain microorganisms. Prebiotics contain enzymes and vitamins to improve digestion and stimulate the growth of beneficial microflora. They are often prescribed for constipation in children and adults.

The group includes those known to practicing doctors: Lactulose, pantothenic acid, Hilak forte, Lysozyme, inulin preparations. Experts believe that it is necessary to combine prebiotics with probiotic preparations to achieve maximum results. For this purpose, combination drugs (synbiotics) have been created.

Characteristics of first generation probiotics

Preparations from the group of first-generation probiotics are prescribed to young children when first-degree dysbiosis is detected, as well as when prevention is necessary, if the patient is prescribed a course of antibiotics.

Primadophilus is an analogue of drugs with two types of lactobacilli, much more expensive than others, since it is produced in the USA

The pediatrician chooses Bifidumbacterin and Lactobacterin for infants (includes bifidobacteria and lactobacilli). They are diluted in warm boiled water and given 30 minutes before breastfeeding. For older children and adults, medications in capsules and tablets are suitable.

Colibacterin - contains dried E. coli bacteria, used for prolonged colitis in adults. The more modern single drug Biobakton contains acidophilus bacillus and is indicated starting from the neonatal period.

Narine, Narine Forte, Narine in milk concentrate - contains the acidophilic form of lactobacilli. Comes from Armenia.

Purpose and description of second generation probiotics

Unlike the first group, second-generation probiotics do not contain beneficial living bacteria, but include other microorganisms that can suppress and destroy pathogenic microflora - yeast-like fungi and bacilli spores.

It is used mainly for the treatment of children with mild dysbacteriosis and intestinal infections. The duration of the course should be no more than seven days, then switch to live bacteria of the first group. Baktisubtil (French drug) and Flonivin BS contain bacillus spores with wide range antibacterial action.

Spores are not destroyed inside the stomach hydrochloric acid and enzymes, reach the small intestine intact

Bactisporin and Sporobacterin are made from Bacillus subtilis, retaining antagonistic properties to pathogenic pathogens and resistance to the action of the antibiotic Rifampicin.

Enterol contains yeast-like fungi (Saccharomycetes). Comes from France. Used in the treatment of diarrhea associated with antibiotics. Active against clostridia. Biosporin includes two types of saprophytic bacteria.

Features of third generation probiotics

Live bacteria or several strains of them collected in combination are more active. Used to treat acute intestinal disorders of moderate severity.

Linex - contains bifidobacteria, lactobacilli and enterococci, produced in Slovakia in a special powder for children (Linex Baby), capsules, sachets. Bifiform is a Danish drug, several varieties are known (Baby drops, chewable tablets, complex). Bifiliz - contains bifidobacteria and lysozyme. Available in suspension (lyophilisate), rectal suppositories.

The drug contains bifidobacteria, enterococci, lactulose, vitamins B 1, B 6

How are fourth generation probiotics different?

When producing preparations with bifidobacteria of this group, the need to create additional protection for the digestive tract and relieve intoxication was taken into account. The products are called “sorbed” because the active bacteria are located on the activated carbon particles.

Indicated for respiratory infections, diseases of the stomach and intestines, dysbacteriosis. The most popular drugs in this group. Bifidumbacterin Forte - contains live bifidobacteria sorbed on activated carbon, available in capsules and powders.

Effectively protects and restores the intestinal flora after respiratory infections, acute gastroenterological pathology, dysbacteriosis. The drug is contraindicated in people with congenital deficiency of the lactase enzyme or rotavirus infection.

Probifor differs from Bifidumbacterin Forte in the number of bifidobacteria; it is 10 times higher than the previous drug. Therefore, the treatment is much more effective. Prescribed for severe forms of intestinal infection, diseases of the large intestine, and dysbacteriosis.

It has been proven that the effectiveness in diseases caused by Shigella is equal to that of fluoroquinolone antibiotics. Can replace the combination of Enterol and Bifiliz. Florin Forte - includes lacto- and bifidobacterial composition, sorbed on coal. Available in capsule and powder form.

Use of synbiotics

Synbiotics are a completely new proposal in the treatment of intestinal flora disorders. They provide a double action: on the one hand, they necessarily contain a probiotic, on the other, they include a prebiotic, which creates favorable conditions for the growth of beneficial bacteria.

The fact is that the effect of probiotics does not last long. After the intestinal microflora is restored, they may die, which again causes the situation to worsen. Accompanying prebiotics feed beneficial bacteria, ensure active growth and protection.

Many synbiotics are considered dietary supplements rather than medicinal substances. Do right choice Only a specialist can. It is not recommended to make treatment decisions on your own. The drugs in this series include the following.

Lb17

Many authors refer to the most the best drugs to date. It combines the beneficial effects of 17 types of living bacteria with extracts of algae, mushrooms, vegetables, medicinal herbs, fruits, and grains (more than 70 components). Recommended for course use, you need to take from 6 to 10 capsules per day.

Production does not involve sublimation and drying, so the viability of all bacteria is preserved. The drug is obtained by natural fermentation for three years. Strains of bacteria work in different areas of the digestion. Suitable for lactose intolerant people, gluten and gelatin free. Supplied to the pharmacy chain from Canada.

Multidophilus plus

Includes three strains of lactobacilli, one - bifidobacteria, maltodextrin. Made in the USA. Available in capsules for adults. The Polish product Maxilac contains: oligofructose as a prebiotic, and live cultures of beneficial bacteria as a probiotic (three strains of bifidobacteria, five strains of lactobacilli, streptococcus). Indicated for diseases of the gastrointestinal tract, respiratory system, and impaired immunity.

Prescribed for children from three years of age and adults, 1 capsule in the evening with meals.

Which probiotics have target indications?

With an abundance of information about bacterial preparations with living microorganisms, some people rush to extremes: either they do not believe in the advisability of use, or, conversely, they spend money on products of little use. It is necessary to consult a specialist about the use of probiotics in a specific situation.

Children with diarrhea during breastfeeding(especially for those born prematurely) liquid probiotics are prescribed. They also help with irregular bowel movements, constipation, and retarded physical development.

Children in such situations are shown:

• Bifidumbacterin Forte;
• Linux;
• Acipol;
• Lactobacterin;
• Biphilis;
• Probifor.

If a child’s diarrhea is associated with a previous respiratory disease, pneumonia, infectious mononucleosis, or false croup, then these drugs are prescribed in a short course for 5 days. For viral hepatitis, treatment lasts from a week to a month. Allergic dermatitis is treated in courses from 7 days (Probifor) to three weeks. A patient with diabetes is recommended to take courses of probiotics of different groups for 6 weeks.

Bifidumbacterin Forte and Bifiliz are most suitable for prophylactic use during the season of increased morbidity.

What is best to take for dysbiosis?

To be sure of a violation of the intestinal flora, it is necessary to take a stool test for dysbacteriosis. The doctor must determine which specific bacteria the body lacks and how severe the disorders are.

If a deficiency of lactobacilli is established, it is not necessary to use only drugs. containing them. Because it is bifidobacteria that determine the imbalance and form the rest of the microflora.

Monopreparations, which contain only the same type of bacteria, are recommended by a doctor only for mild disorders

In severe cases it is necessary combined agents third and fourth generation. Probifor is most indicated (infectious enterocolitis, colitis). For children, it is always necessary to select combinations of drugs with lacto- and bifidobacteria.

Products containing colibacteria are prescribed very carefully. When identifying ulcers in the intestines and stomach, acute gastroenteritis, probiotics with lactobacilli are more indicated.

Typically, the doctor determines the duration of treatment based on the generation of the probiotic:

• I – a monthly course is required.
• II – from 5 to 10 days.
• III – IV - up to seven days.

If there is no effectiveness, the specialist changes the treatment regimen, adds antifungals and antiseptics. The use of probiotics is a modern approach to the treatment of many diseases. This is especially important for parents of young children to remember. It is necessary to distinguish medicines from biological food additives. Existing dietary supplements with intestinal bacteria can only be used healthy person for the purpose of prevention.

Structure

Bacteria are very small living organisms. They can only be seen under a microscope with very high magnification. All bacteria are unicellular. The internal structure of a bacterial cell is not similar to plant and animal cells. They have neither a nucleus nor plastids. Nuclear matter and pigments are present, but in a “sprayed” state. The form is varied.

The bacterial cell is covered with a special dense shell - a cell wall, which performs protective and supporting functions, and also gives the bacterium a permanent, characteristic shape. The cell wall of a bacterium resembles the wall of a plant cell. It is permeable: through it, nutrients freely pass into the cell, and metabolic products exit into the environment. Often, bacteria produce an additional protective layer of mucus on top of the cell wall - a capsule. The thickness of the capsule can be many times greater than the diameter of the cell itself, but it can also be very small. The capsule is not an essential part of the cell; it is formed depending on the conditions in which the bacteria find themselves. It protects the bacteria from drying out.

On the surface of some bacteria there are long flagella (one, two or many) or short thin villi. The length of the flagella can be many times greater than the size of the body of the bacterium. Bacteria move with the help of flagella and villi.

Inside the bacterial cell there is dense, immobile cytoplasm. It has a layered structure, there are no vacuoles, therefore various proteins (enzymes) and reserve nutrients are located in the substance of the cytoplasm itself. Bacterial cells do not have a nucleus. A substance carrying hereditary information is concentrated in the central part of their cell. Bacteria - nucleic acid - DNA. But this substance is not formed into a nucleus.

The internal organization of a bacterial cell is complex and has its own specific characteristics. The cytoplasm is separated from the cell wall by the cytoplasmic membrane. In the cytoplasm there is a main substance, or matrix, ribosomes and a small number of membrane structures that perform a variety of functions (analogues of mitochondria, endoplasmic reticulum, Golgi apparatus). The cytoplasm of bacterial cells often contains granules of various shapes and sizes. The granules may be composed of compounds that serve as a source of energy and carbon. Droplets of fat are also found in the bacterial cell.

Education dispute

Spores form inside the bacterial cell. During the process of sporulation, the bacterial cell undergoes a number of biochemical processes. It reduces the amount free water, enzymatic activity decreases. This ensures the resistance of the spores to unfavorable environmental conditions (high temperature, high salt concentration, drying, etc.). Sporulation is characteristic of only a small group of bacteria. Spores are an optional stage in the life cycle of bacteria. Sporulation begins only with a lack of nutrients or accumulation of metabolic products. Bacteria in the form of spores can remain dormant for a long time. Bacterial spores can withstand prolonged boiling and very long freezing. When favorable conditions occur, the spore germinates and becomes viable. Bacterial spores are an adaptation to survival in unfavorable conditions. Bacterial spores serve to survive unfavorable conditions. They are formed from the interior of the cell contents. At the same time, a new, denser shell is formed around the spore. Spores can be very low temperatures(up to - 273 °C) and very high. Spores are not killed by boiling water.

Nutrition

Many bacteria have chlorophyll and other pigments. They carry out photosynthesis, like plants (cyanobacteria, purple bacteria). Other bacteria obtain energy from inorganic substances - sulfur, iron compounds and others, but the source of carbon, as in photosynthesis, is carbon dioxide.

Reproduction

Bacteria reproduce by dividing one cell into two. Having reached a certain size, the bacterium divides into two identical bacteria. Then each of them begins to feed, grows, divides, and so on. After cell elongation, a transverse septum gradually forms, and then the daughter cells separate; In many bacteria, under certain conditions, after dividing, cells remain connected in characteristic groups. In this case, depending on the direction of the division plane and the number of divisions, different shapes arise. Reproduction by budding occurs as an exception in bacteria.

Under favorable conditions, cell division in many bacteria occurs every 20-30 minutes. With such rapid reproduction, the offspring of one bacterium in 5 days is capable of forming a mass that can fill all seas and oceans. A simple calculation shows that 72 generations (720,000,000,000,000,000,000 cells) can be formed per day. If converted into weight - 4720 tons. However, this does not happen in nature, since most bacteria quickly die when exposed to sunlight, during drying, lack of food, heating to 65-100ºС, as a result of struggle between species, etc.

The role of bacteria in nature. Distribution and ecology

Bacteria are distributed everywhere: in water bodies, air, soil. There are fewer of them in the air (but not in crowded places). In river waters there can be up to 400,000 per 1 cm3, and in soil - up to 1,000,000,000 per 1 g. Bacteria have different attitudes towards oxygen: for some it is necessary, for others it is destructive. For most bacteria, temperatures between +4 and +40 °C are most favorable. Direct sunlight kills many bacteria.

Occurring in huge numbers (the number of their species reaches 2500), bacteria play exclusively important role In many natural processes. Together with fungi and soil invertebrates, they participate in the processes of decomposition of plant residues (falling leaves, branches, etc.) to humus. The activity of saprophytic bacteria leads to the formation of mineral salts, which are absorbed by plant roots. Nodule bacteria living in the tissues of the roots of moths, as well as some free-living bacteria, have a remarkable ability to assimilate atmospheric nitrogen, which is inaccessible to plants. Thus, bacteria participate in the cycle of substances in nature.

Soil microflora. The number of bacteria in the soil is extremely large - hundreds of millions and billions of individuals per gram. There are much more of them in soil than in water and air. Total bacteria in soils is changing. The number of bacteria depends on the type of soil, their condition, and the depth of the layers. On the surface of soil particles, microorganisms are located in small microcolonies (20-100 cells each). They often develop in the thickness of clots of organic matter, on living and dying plant roots, in thin capillaries and inside lumps. The soil microflora is very diverse. Here there are different physiological groups of bacteria: putrefaction bacteria, nitrifying bacteria, nitrogen-fixing bacteria, sulfur bacteria, etc. among them there are aerobes and anaerobes, spore and non-spore forms. Microflora is one of the factors in soil formation. The area of ​​development of microorganisms in the soil is the zone adjacent to the roots of living plants. It is called the rhizosphere, and the totality of microorganisms contained in it is called the rhizosphere microflora.

Microflora of water bodies. Water is a natural environment where microorganisms develop in large numbers. The bulk of them enters the water from the soil. A factor that determines the number of bacteria in water and the presence of nutrients in it. The purest waters are artesian wells and spring. Open reservoirs and rivers are very rich in bacteria. The largest number of bacteria is found in the surface layers of water, closer to the shore. As you move away from the shore and increase in depth, the number of bacteria decreases. Pure water contains 100-200 bacteria in 1 ml, and contaminated - 100-300 thousand or more. There are many bacteria in the bottom sludge, especially in the surface layer, where the bacteria form a film. This film contains a lot of sulfur and iron bacteria, which oxidize hydrogen sulfide to sulfuric acid and thereby prevent fish from dying. There are more spore-bearing forms in silt, while non-spore-bearing forms predominate in water. In terms of species composition, the water microflora is similar to the soil microflora, but there are also specific forms. By destroying various waste that gets into the water, microorganisms gradually carry out the so-called biological purification of water.

Air microflora. The microflora of the air is less numerous than the microflora of soil and water. Bacteria rise into the air with dust, can remain there for some time, and then settle on the surface of the earth and die from lack of nutrition or under the influence of ultraviolet rays. The number of microorganisms in the air depends on geographical area, terrain, time of year, dust pollution, etc. every speck of dust is a carrier of microorganisms. Most bacteria are in the air above industrial enterprises. Air rural areas cleaner. The cleanest air is over forests, mountains, and snowy areas. The upper layers of air contain fewer microbes. The air microflora contains many pigmented and spore-bearing bacteria, which are more resistant than others to ultraviolet rays.

Microflora of the human body. The human body, even a completely healthy one, is always a carrier of microflora. When the human body comes into contact with air and soil, various microorganisms, including pathogenic ones (tetanus bacilli, gas gangrene, etc.), settle on clothing and skin. The most frequently exposed parts of the human body are contaminated. E. coli and staphylococci are found on the hands. IN oral cavity There are over 100 species of microbes. The mouth, with its temperature, humidity, and nutrient residues, is an excellent environment for the development of microorganisms. The stomach has an acidic reaction, so the majority of microorganisms in it die. Starting from the small intestine, the reaction becomes alkaline, i.e. favorable for microbes. The microflora in the large intestines is very diverse. Each adult excretes about 18 billion bacteria daily in excrement, i.e. more individuals than people on the globe. Internal organs, not connecting with external environment(brain, heart, liver, bladder, etc.) are usually free of germs. Microbes enter these organs only during illness.

The importance of bacteria in human life

Fermentation processes are of great importance; This is what is generally called the decomposition of carbohydrates. So, as a result of fermentation, milk turns into kefir and other products; Ensilage of feed is also fermentation. Fermentation also occurs in the human intestine. Without appropriate bacteria (for example, E. coli), the intestines cannot function normally. Rotting, useful in nature, is extremely undesirable in everyday life (for example, spoilage meat products). Fermentation (for example, souring milk) is not always beneficial. To prevent food from spoiling, they are salted, dried, canned, and kept in refrigerators. This reduces the activity of bacteria.

Pathogenic bacteria

Most people associate the word “bacteria” with something unpleasant and a threat to health. At best, fermented milk products come to mind. At worst - dysbacteriosis, plague, dysentery and other troubles. But bacteria are everywhere, they are good and bad. What can microorganisms hide?

What are bacteria

Bacteria means “stick” in Greek. This name does not mean that harmful bacteria are meant. They were given this name because of their shape. Most of these single cells look like rods. They also come in the form of triangles, squares, and star-shaped cells. For a billion years, bacteria do not change appearance, can only change internally. They can be movable or immobile. A bacterium consists of one cell. On the outside it is covered with a thin shell. This allows it to maintain its shape. There is no nucleus or chlorophyll inside the cell. There are ribosomes, vacuoles, cytoplasmic outgrowths, and protoplasm. The largest bacterium was found in 1999. It was called the "Grey Pearl of Namibia". Bacteria and bacillus mean the same thing, they just have different origins.

Man and bacteria

In our body there is a constant battle between harmful and beneficial bacteria. Thanks to this process, a person receives protection from various infections. Various microorganisms surround us at every step. They live on clothes, 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 develop gynecological diseases. Following basic rules of personal hygiene will help avoid such failures.

Human immunity completely depends on the state of the microflora. Almost 60% of all bacteria are found in the gastrointestinal tract alone. The rest settled in respiratory system and in the genital area. About two kilograms of bacteria live in a person.

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 previously unfamiliar. When the baby is first put 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 feeding as long as possible.

Beneficial bacteria

Beneficial bacteria are: lactic acid bacteria, bifidobacteria, E. coli, streptomycents, mycorrhizae, cyanobacteria.

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

Types of harmful bacteria

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

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

Names of harmful bacteria

Harmful bacteria can for a long time reside in the body and absorb beneficial substances from it. However, they can cause 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 can cause not one, but several infectious diseases. Some types of these bacteria are resistant to powerful antibiotics and antiseptics. Strains of this bacterium can live in the upper respiratory tract, open wounds and urinary tract of every third inhabitant of the Earth. For a person with a strong immune system, this does not pose a danger.

Harmful bacteria to humans are also pathogens called Salmonella typhi. They are the causative agents of acute intestinal infections and typhoid fever. These types of bacteria, harmful to humans, are dangerous because they produce toxic substances that are extremely dangerous to life. As the disease progresses, intoxication of the body occurs, very high fever, rashes on the body, and the liver and spleen enlarge. The bacterium is very resistant to various external influences. Lives well in water, on vegetables, fruits and reproduces well in milk products.

Clostridium tetan is also one of the most dangerous bacteria. It 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 on Earth.

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

Measures to prevent the spread of infections

Harmful bacteria and the names of microorganisms are studied by doctors of all disciplines from their student days. Healthcare annually seeks new methods to prevent the spread of life-threatening infections. If you follow preventive measures, you will not have to waste energy on finding new ways to combat such diseases.

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

The second stage is the destruction of pathways through which harmful bacteria can be transmitted. For this purpose, appropriate propaganda is carried out among the population.

Food facilities, reservoirs, and food storage warehouses are taken under control.

Every person can resist harmful bacteria by strengthening their immunity in every possible way. A healthy lifestyle, observing basic hygiene rules, protecting yourself during sexual contact, using sterile disposable medical instruments and equipment, completely limiting communication with people in quarantine. If you enter an epidemiological area or a source of infection, you must strictly comply with all the requirements of sanitary and epidemiological services. A number of infections are equated in their effects to bacteriological weapons.

Beneficial bacteria

Scientists say that bacteria became the very first inhabitants of our big 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. 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 characterized by some harmony, because such organisms are capable of bringing real benefits.

After small man is born, bacteria immediately begin to penetrate into his body. They penetrate the respiratory tract along with the air and enter the body along with breast milk etc. The whole body becomes saturated with different bacteria.

It is impossible to accurately calculate their number, but some scientists boldly say that the number of such cells in the body is comparable to the number of all cells. The digestive tract alone is home to four hundred different types of living bacteria. It is believed that a certain variety can grow only in a specific place. Thus, lactic acid bacteria are able to grow and multiply in the intestines, others feel optimal in the oral cavity, and some live only on the skin.

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

Bacteria are capable of collecting particles of various cells on their surface, which is why the immune system does not perceive them as hostile and does not attack them. However, after organs and systems are exposed to harmful viruses, beneficial bacteria rise to the defense and simply block the path of pathogens. When existing in the digestive tract, such substances also bring tangible benefits. They process leftover food, releasing a significant amount of heat. It, in turn, is transmitted to nearby organs, and is transferred throughout the body.

A deficiency of beneficial bacteria in the body or a change in their number causes the development of various pathological conditions. This situation can develop while 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 many dangerous varieties that can only cause harm. Such organisms, after entering our body, become the cause of the development of various bacterial ailments. These include various colds, some types of pneumonia, and also syphilis, tetanus and other diseases, even deadly ones. There are also diseases of this type that are transmitted by airborne droplets. This is dangerous tuberculosis, whooping cough, etc.

A significant number of ailments caused by harmful bacteria develop due to the consumption of insufficiently high-quality food, unwashed and unprocessed vegetables and fruits, raw water, and undercooked meat. You can protect yourself from such diseases by following the rules and regulations of hygiene. Examples of such dangerous illnesses are dysentery, typhoid fever, etc.

Manifestations of diseases that develop 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 its natural defense, which is based on the process of phagocytosis of bacteria by white blood cells, as well as on the immune system, which synthesizes antibodies. The latter bind foreign proteins and carbohydrates, and then simply eliminate them from the bloodstream.

Also, harmful bacteria can be destroyed using natural and synthetic medications, the most famous of which is penicillin. All drugs of this type are antibiotics; they differ depending on the active component and the mode of action. Some of them are capable of destroying the cell membranes of bacteria, while others suspend their vital processes.

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

Help me, I need a brief description of beneficial and harmful bacteria, all of them are not covered, they are not missing, please help me

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

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

Useful; For thousands of years, people have used lactic acid bacteria to produce cheese, yogurt, kefir, vinegar, and fermentation.

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

Bacteria that cause human disease are used as biological weapons.

Due to their rapid growth and reproduction, as well as their simple structure, bacteria are actively used in scientific research in molecular biology, genetics, genetic engineering and biochemistry. The most well-studied bacterium is Escherichia coli. Information about bacterial metabolic processes has 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 petroleum products or xenobiotics by bacteria.

The human intestine normally contains from 300 to 1000 species of bacteria with a total mass of up to 1 kg, and the number of their cells is an order of magnitude greater 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.

It's not entirely short. but I think you can shorten it as you like.

There are bacteria that are very beneficial. Each person’s body contains from one and a half to two and a half kilograms of such bacteria. Communities of bacteria are called microbiota; their number reaches several million. They affect the healthy and normal functioning of the body. Without them, the skin, gastrointestinal tract, and respiratory tract would be destroyed by pathogenic microorganisms.

Beneficial bacteria living in the intestines

The entire immune system of the body depends on the normal functioning of the gastrointestinal tract. Protective processes are reduced and the immune system is destabilized if the species composition of the microbiota in the body is disturbed. Beneficial bacteria create an acidic environment in the intestines, which is harmful to pathogens. In addition, beneficial bacteria help digest and absorb plant foods, which intestinal enzymes cannot cope with on their own. These bacteria are involved in the production of vitamins that support metabolic processes in connective tissue, help extract energy from carbohydrates, regulate the activity of the nervous system, and promote the production of antigens.

When they talk about beneficial intestinal bacteria, they mean two types of bacteria - bifidobacteria and lactobacilli, which make up from 5% to 15% of the total number of intestinal bacteria. Their activity is extremely important because they have a positive effect on other microorganisms and stabilize the intestinal microflora. It is important to maintain the number of fermented milk bacteria by eating kefir and yoghurt, which will promote the reproduction and strengthening of the intestinal microflora. It is extremely important to consume foods containing lactobacilli for dysbiosis after taking antibiotics. Otherwise, it is very difficult to restore immune processes

Biological shield

Many beneficial bacteria inhabit human epithelial tissues, both internal and external. They are at the forefront of defense and prevent the penetration of pathogenic microorganisms. The main such bacteria are staphylococcus streptococci and micrococci.

The human microflora has changed significantly as we move from natural to urban living, and frequently use detergents. Thus, bacteria modern man and the person who lived in the past are significantly different. The body has learned to distinguish dangerous species from not dangerous, but any streptococcus that enters the bloodstream can cause serious illness. It should be noted that an excess of bacteria both on the skin and in the respiratory tract can cause various ailments and an unpleasant odor. To date, special microorganisms have been identified that can oxidize ammonium. Regular use of preparations with such bacteria promotes the colonization of the skin with new organisms, as a result of which not only diseases and unpleasant odors disappear, but also the structure of the skin changes, for example, pores open.

The microflora of each person changes very quickly depending on the individual characteristics of the body and the environment in which it is located. This can be seen as both pros and cons, since the number and species composition of bacteria can change independently. Different microorganisms require different substances. The more diverse a person’s food is, the more it is tied to the seasonal range of products, the more beneficial microorganisms there will be. But if food is saturated with antibiotics, preservatives, and various chemical dyes, then the bacteria cannot withstand such a load and may die. In this case, both pathogenic and beneficial organisms disappear. As a result, the human microflora is destroyed, which leads to the emergence of various diseases.

However, the body's microbes can be helped. This does not require long months and only a few days. Today, biotechnological production has created a large number of probiotics, which contain live bacteria and prebiotics - products that support the vital activity of bacteria. The only problem is that these substances work differently for each person. Studies show that the use of these products for dysbiosis can improve the body's condition by 80%, or may have no effect at all. As soon as the substances begin to act, a person will immediately feel an improvement in his condition. However, if the situation does not change, then it is worth adjusting the treatment system. There are special tests that are aimed at determining the genome of bacteria. They help identify the necessary nutritional option and additional bacterial therapy to establish the balance of microorganisms in the body.

Often a person does not feel a disturbance in the bacterial microclimate, but if there is drowsiness, frequent illnesses or allergic reactions, then all this indicates dysbacteriosis. Residents of cities and megalopolises are especially susceptible to such disorders of the body's microflora, and if nothing is done, health problems will certainly arise. The microflora is positively influenced by fasting diets, fasting, food enriched with vegetables, natural cereals and porridges, fermented milk products, etc.

Harmful microorganisms

The first microorganisms appeared on Earth several billion years ago. Through evolution, they improved and mastered new habitats. Now prokaryotes are ubiquitous. High degree survival is due to the presence of “jumping genes” that carry acquired achievements. Microorganisms are capable of transmitting such genes to each other from generation to generation.

Human microflora

Man and bacteria exist inseparably with each other. Protozoa can cause both benefit and harm. Of all the known bacteria found on the surface and inside the human body, 99% are beneficial and only 1% are pathogenic microflora. However, it is this small part that causes significant damage to health and therefore the mere mention of the word “bacteria” is negative. Microbes exist everywhere: in the bladder, vagina, respiratory tract, intestines, mucous membranes, etc. The necessary balance is maintained by special bacteria that provide immunity, protecting the human body from the action of pathogens.

Harmful airborne bacteria

Since the air environment is not natural environment In the habitat of bacteria, they remain in the air temporarily, entering it from the soil, from plants, animals. The infection is spread by airborne droplets. This is how bacterial and viral infections, various protozoa, and fungi can be transmitted. These microorganisms cause diseases such as chickenpox, influenza, scarlet fever, tuberculosis, whooping cough, streptococcal infections, etc.

Harmful bacteria in water

The aquatic environment is good place habitat for various bacteria. There are a million different microbes in one cubic centimeter. Harmful microbes enter the water from industrial enterprises, with agricultural waste, waste emissions settlements. Contaminated water is a dangerous source of cholera, dysentery, diphtheria, measles and other dangerous diseases. It should be noted that the causative agents of cholera or tuberculosis can remain in the aquatic environment for a significant amount of time.

Harmful soil bacteria

Soil is the natural habitat of bacteria. In the surface layer (30 cm) of one hectare of land there are about 30 tons of microorganisms. Among them may be useful, breaking down plant residues into amino acids. So they take Active participation in the processes of decay. However, many of the bacteria are harmful to humans, for example, they affect food. To prevent spoilage, special processing of products is necessary, for example, sterilization, smoking, freezing or salting. Some species are so active that they can even attack frozen or salted foods, causing dangerous diseases such as botulism, tetanus, various types of gangrene and anthrax.

Harmful bacteria that damage wood

Microorganisms naturally, thanks to the presence of special enzymes, are able to decompose cellulose fiber. Such saprophytes include mushrooms. Some can paint wood in different colors, while affecting wooden buildings, which contributes to their rapid destruction. The activity of such fungi is especially active in wooden agricultural structures.

Harmful food bacteria

Products containing harmful bacteria are dangerous sources of disease and can cause diseases such as salmonellosis, dysentery, typhoid fever, cholera and many others. For example, botulism toxins cause severe toxicological damage to the body, butyric acid bacteria spoil cheeses and dairy products, causing them to deteriorate, develop an unpleasant odor, and change color. The vinegar stick causes souring of low-alcohol products, such as beer and wine. Micrococci cause rotting of proteins and the appearance of a putrid odor. Molds are widespread, affecting protein and carbohydrate products manufactured by humans.