What bacteria cause bacteria? Human Diseases caused by Bacteria

There are five main kingdoms of wildlife, whose representatives have been carefully studied for many centuries. It:

• animals;
• plants;
• mushrooms;
• bacteria, or prokaryotes;
• viruses.

If animals, plants and fungi were known to people from the very time of primordial age, then people began to study viruses and bacteria relatively recently. These organisms are too small to be able to be studied with the naked eye. That is why they have been hidden for so long from the vigilant gaze of mankind.

It is known that they play by no means only a positive role. So we will try to understand the question of which bacteria are the causative agents of which diseases, and how these creatures are generally arranged and live.

Who are the prokaryotes?

All living creatures on our planet are united by a commonality in the structure - they consist of cells. True, part of all of one, the other part - multicellular. If we talk about multicellular animals, then everything is the same. Each such organism has a decorated nucleus in its cells. But when it comes to unicellular organisms, then there is no such unity, since they are divided into eukaryotes and prokaryotes.

Eukaryotes include all living things whose cells have hereditary material fixed in the nucleus. To prokaryotes, such unicellular organisms in which DNA is distributed freely, is not limited to the nuclear membrane, and therefore does not have a nucleus as a whole. These creatures include:

• blue-green algae;
• cyanobacteria;
• archebacteria;
• bacteria.

Initially, only such organisms lived on the planet. But gradually evolution came to the appearance of eukaryotic multicellular organisms, inside which remained prokaryotic cells. Then, uniting together and concluding a symbiotic relationship, they became a wonderful, strong, resistant to environmental conditions organism, ready for self-reproduction and increase in numbers, evolution.

The proof of this theory is such non-nuclear multicellular cell organelles as mitochondria and plastids (chloroplasts, chromoplasts, leukoplasts).

But, unfortunately, many of the prokaryotic cells are not as harmless to plants, animals and people as those that remained to live inside them. They got the modern name of bacteria, or microbes, and began to live an independent life, causing a lot of trouble for highly organized creatures.

Many diseases associated with bacteria and their vital functions are known. Moreover, not only in humans, but also among representatives of all other kingdoms of wildlife.

A brief outline of the discovery story

Bacteria have been around for more than 3.5 billion years. During this time, nothing has changed in their structure. The only thing that has become new in their lives is their fame for man.

How did the discovery of these organisms occur? Let's consider in stages.

1. Even the ancient Greek scientist Aristotle spoke of the fact that there are creatures invisible to the eye that live on everything around, including humans. They can cause illness.
2. 1546 - Italian doctor Girolamo Fracostoro suggested that human diseases are caused by tiny organisms, microbes. However, he could not prove it and remained unheard.
3. 1676 - Antonio van Levenguk studied a section of a cork tree under a microscope invented with his own hands (the first microscope of its production was very large and resembled a collection of several differently located mirrors, it gave an increase of more than a hundred times). As a result, he managed to see the cells that make up the tree bark. And also, looking at a drop of water, he examined the many tiny organisms that lived in this drop. These were the bacteria to which he gave the name "animalkuli".
4. 1840 - the German doctor Jacob Henle puts forward a completely correct hypothesis about the action of pathogenic microorganisms on humans, that is, that bacteria are pathogens.
5. 1862 - French chemist Louis Pasteur, as a result of repeated experiments, proved the presence of microorganisms in all environments, objects, organisms. Thus, he confirmed the hypothesis of Henle, and it has already become a theory called the Microbial Theory of Diseases. For his work, the scientist was awarded the Nobel Prize.
6. 1877 - Robert Koch introduces a method for staining bacterial cultures.
7. 1884 - Hans Gram, a doctor. It belongs to him the merit of dividing these creatures into gram-positive and gram-negative, depending on the reaction to the type of dye.
8. 1880 - Karg Ebert revealed the cause of typhoid fever - the action of rod-shaped bacteria.
9. 1882 - Robert Koch isolates tubercle bacillus.
10. 1897 - Japanese doctor Kie-si Shiga discovered the cause of dysentery
11. 1897 - Bernhard Bang established the fact that there are bacteria that cause animal diseases that cause miscarriages in them.

Thus, the development of knowledge about bacteria and the diseases they cause is gaining rapid momentum. And today more than 10 thousand different representatives of prokaryotes have already been described. However, scientists predict that there are more than a million species in the world.

Prokaryotic Sciences

Bacteria as causative agents of infectious diseases have always been of interest to science, because knowledge of them can solve many health problems not only of humans, but also of animals and plants. Therefore, several sciences have been formed that are studying this issue.

1. Microbiology is a general science that studies all microscopic organisms, including bacteria.
2. Bacteriology is a science that studies microbes, bacteria, their diversity, lifestyle, distribution and impact on the outside world.
3. Sanitary microbiology - studies preventive measures for the development of bacterial diseases in humans.
4. Veterinary microbiology - explores the pathogens of infectious diseases in animals, ways to eliminate, treat, prevent infection.
5. Medical Microbiology - considers the effect of bacteria on the life of all living things from a medical point of view.

In addition to bacterial cells, there are also unicellular protozoa, pathogens in humans, animals and plants. For example, amoeba, malarial plasmodium, trypanosomes and so on. These are also objects of study of medical microbiology.

What are the bacteria?

There are two bases for the classification of bacterial cells. The first is built on the principle of separation of microbes that are diverse in cell shape. So, on this basis, there are:

• Cocci, or spherical, spherical organisms. Several varieties are also included here: diplococci, streptococci, staphylococci, micrococci, sarcinomas, tetracocci. The sizes of such representatives do not exceed 1 μm. It is to this group that the majority of those who are called "causative agents of human diseases" belong.
• Sticks, or rod-shaped bacteria. Varieties in the shape of the ends of the cell: regular, pointed, club-shaped, vibrios, cropped, rounded, chain-shaped. All these bacteria are pathogens. What kind of illness? Almost all infectious diseases known to humans today.
• Twisted organisms. Subdivided into spirill and spirochete. Thin convoluted spiral structures, some of which are pathogenic microbes, and the other, representatives of the normal intestinal microflora of animals and humans.
• Branching bacteria - basically resemble rod-shaped forms, but at the end they have branches of varying degrees. These include bifidobacteria, which play a positive role in people's lives.

Another classification of bacterial cells is based on modern indicators: RNA in structure, biochemical and morphological properties, in relation to staining, and so on. According to these signs, all bacteria can be divided into 23 types, each of which includes several classes, genera and species.

It is also possible to classify microorganisms by the method of nutrition, by the type of respiration, by the occupied habitat, and so on.

Human use of bacteria

People have learned to use microorganisms since ancient times. On their part, it was, of course, not a purposeful application, but simply a profitable acquisition from nature. So, for example, alcoholic beverages were produced, fermentation processes took place.

With the passage of time and the disclosure of the life mechanisms of these tiny creatures, man has learned to more fully apply them in his needs. There are several branches of the economy with which biology is closely intertwined. Bacteria are used:

1. In the food industry: baking confectionery and bread, winemaking, dairy products and so on.
2. Chemical synthesis: bacteria produce amino acids, organic acids, proteins, vitamins, lipids, antibiotics, enzymes, pigments, nucleic acids, sugars, and so on.
3. Medicine: drugs that restore the microflora of the internal environment of the body, antibiotics and so on.
4. Agriculture: preparations for plant growth and animal treatment, strains of bacteria that increase yield, milk yield and egg production, and so on.
5. Ecology: oil-degrading microorganisms that process organic and inorganic residues, purification of the environment.

However, in addition to the positive effects of using bacteria, people cannot get rid of the negative ones. After all, bacteria are the causative agents of what human diseases? The most difficult, dangerous and sometimes fatal. Therefore, their role in nature and human life is dual.

Pathogenic Microbes: General Description

Pathogenic bacteria include those microbes that can cause damage to tissues and internal systems of organs in humans and animals. In their external and internal structure, they are no different from beneficial bacteria: a single-celled structure, covered with a dense shell (cell wall), is externally clad in a mucus capsule that protects from digestion inside the host and from drying out. Genetic material is distributed within the cell in the form of a chain of a DNA molecule. Under adverse conditions, they are able to form disputes - to fall into a state of numbness in which the processes of vital activity cease until the resumption of favorable conditions.

What bacteria cause pathogens of living creatures? Those that are easily transmitted by airborne droplets, by direct contact or by contact with exposed mucous areas of the skin. And this means that pathogens can be called weapons of mass destruction. After all, it is they who are capable of causing entire epidemics, pandemics, epizootics, epiphytoties, and so on. That is, diseases covering entire countries that affect plants (epiphytoties), and animals (epizootics), and humans (epidemics).

Unfortunately, not all species of such creatures have yet been fully studied by man. Therefore, there is no guarantee that at any moment there will be no infection unknown to people. This places even greater responsibility on microbiologists, medical researchers, and virologists.

What diseases do bacteria cause?

There are many such diseases. However, it is impossible to distinguish only some common ones. After all, bacteria are able to infect not only animals, but also plant tissues. Therefore, all the diseases that they cause are usually divided into several groups.

1. Anthroponic infections are those that are characteristic only for people, and infection is possible strictly between them (human pathogens). Examples of diseases: typhoid, cholera, smallpox, measles, dysentery, diphtheria and others.
2. Zoonotic diseases are infections that animals suffer from and which they carry within themselves, but at the same time they can infect humans. So, for example, with the bites of insects or other animals, with the contact of animals with the skin and respiratory tract of a person, bacterial spores are transmitted. Diseases: glanders, anthrax, plague, tularemia, rabies, foot and mouth disease.
3. Epiphytic infections are plant diseases caused by bacteria. These include rot, spotting, tumors, burns, gummosis and other bacterioses.

Consider human diseases caused by bacteria. Those that are the most common. It was they who brought in the past and present many troubles and troubles to people.

Human bacteria

Human diseases caused by bacteria have always done a lot of harm and damage to human health. The most common and dangerous of them are the following:

1. Plague is a terrible word for residents of the Middle Ages and Renaissance. This disease claimed thousands of lives. Previously, getting the plague was tantamount to death, until you came up with a way to vaccinate and a cure for this terrible infectious disease. Now this disease occurs in some tropical countries and is strictly zoonotic in nature.
2. Erysipelas is a disease of animals, mainly pigs, chickens, lambs, horses. It is transmitted to humans. It is caused by pathogenic bacteria, the names of which are Erysipelothrix insidiosa. The fight against the disease is simple, these pathogens are afraid of direct sunlight, high temperatures and alkalis. Currently, the disease is not too common. The occurrence of foci depends on the conditions of the animals.
3. Diphtheria. A dangerous disease of the upper respiratory tract, gives a strong complication to the heart. Today it is quite rare, since vaccination is carried out in the early stages of a child's development.
4. Dysentery. Bacteria called Shigella (Shigella) cause this disease. The source of infection is sick people who are able to transmit the infection through a household, water or contact route (by mouth). Children are most susceptible to the disease. You can get dysentery several times, since the immunity to the disease is only temporary.
5. Tularemia - caused by the bacteria Francisella tularensis. Very tenacious, resistant to temperatures, environmental conditions, infection. The treatment is complex, not fully developed.
6. Tuberculosis - caused by Koch's wand. A complex disease that affects the lungs and other organs. Healing systems are developed and widely practiced, but so far it has not been possible to completely eradicate the ailment.
7. Whooping cough is an infection caused by the bacterium Bordetella pertussis. It is characterized by the appearance of severe coughing attacks. Vaccination in early childhood.
8. Syphilis is a very common sexually transmitted infection. Caused by the pathogen spirochete trypanosome. It affects the genitals, eyes, skin, central nervous system, bones and joints. Antibiotic treatment, medicine is known.
9. Gonorrhea is just like syphilis, a disease of the 21st century. Sexually transmitted, antibiotic treatment. Called by gonococcus bacteria.
10. Tetanus - caused by the stick of Clostridium tetani, which releases the strongest toxins into the human body. This leads to terrible cramps and uncontrolled muscle contractions.

Of course, there are other bacteria and human diseases. But the listed are the most common and serious.

Animal germs

The most common animal diseases caused by bacteria include:

• botulism;
• tetanus;
• pasteurellosis;
• colibacillosis;
• Bubonic plague;
• glanders;
• melioidosis;
• yersiniosis;
• vibriosis;
• actinomycosis;
• anthrax;
• foot and mouth disease.

All of them are caused by certain bacteria. Diseases for the most part are transmitted to people, therefore they are extremely dangerous and serious. The main measures to prevent the spread of such diseases are keeping the animals clean, carefully caring for them, and limiting contact with the sick.

Plant germs

Among the harmful microbes that infect the root systems and shoots of plants and thereby cause serious damage to agriculture, the most common are the following representatives:

• Mycobacteriaceae;
• Pseudomonadaceae;
• Bacteriaceae.

Plant diseases caused by bacteria cause rotting and death of the following parts of cultivated plants:

• roots
• leaves;
• stems;
• fruits;
• inflorescences;
• root crops.

That is, the whole plant can be affected by the pathogen. Most often, agricultural crops such as potatoes, cabbage, corn, wheat, onions, tomatoes, shag, grapes, various fruit trees and other fruits, vegetables, and crops are affected.

The main diseases include the following:

• bacteriosis;
• crayfish;
• bacterial spotting;
• rot;
• mountain ash;
• basal bacteriosis;
• bacterial burn;
• ring rot;
• black leg;
• gummosis;
• striped bacteriosis;
• black bacteriosis and others.

Currently, botanists and agricultural microbiologists are actively working to find plant protection products from these scourges.