Unicellular mushrooms and their role in nature

Unicellular organisms became known to man only with the advent of magnifying devices. However, today they are the basis of valuable genetic research for the accumulation of theoretical material on many issues of biochemistry, molecular biology, genetics. There are different unicellular organisms. Mushrooms are one of them. Not all, of course, but a rather significant part. In this article, we consider which representatives are included in the category of protozoa and what properties and features they possess.

Unicellular and multicellular mushrooms: general characteristics

Of all the five kingdoms of wildlife, mushrooms are the most unusual. The thing is that it is quite simple to determine the systematic position of a plant or animal. Bacteria and viruses have a completely different structure, so there can be no mistakes at all.

And only mushrooms are such complex organisms that for a long time did not belong to any particular kingdom. Initially, they were considered plants simply devoid of chlorophyll. More recent studies have shown that their decay products contain urea, and the cell wall is largely composed of chitin. At the same time, digestion is external, and many enzymes are akin to those produced by mammalian organisms.

These signs clearly spoke of the belonging of mushrooms to animals. In addition, it became known that unicellular fungi of the myxomycetes department (mucus) are able to move towards food and light under certain conditions. This once again proves that these organisms and animals had a common ancestor.

All this led to the fact that mushrooms began to be attributed to a separate kingdom of wildlife. A common sign for their identification is:

• the presence of unicellular multicore or multicellular mycelium;
• GIFs - thin threads that can intertwine, forming a mycelium and fruiting body;
• heterotrophic diet;
• chitin in the cell wall;
• urea as a part of decomposition products;
• lack of plastids;
• reproduction through spores.

In total, today there are about 250 thousand species of these organisms. A significant part of them is unicellular mushrooms.

Classification of unicellular fungi

With such a variety, there is a need for classification. Therefore, all unicellular mushrooms were systematized, examples of which can be given if we consider the full classification.

Today, it doesn’t exist as a single entity; therefore, they are not the same for different authors. So, there are 4 main groups.

1. Deuteromycetes is another name for imperfect mushrooms. They do not have sexual reproduction. Representatives: sclerotium, rhizoctonia, many types of candida.
2. Chitridiomycetes are complex unicellular fungi whose mycelium is represented by long branching structures containing several nuclei. Representatives: olpidium, silchithrium, spizellomas, monoblefarids and others. Most lead an aquatic or semi-aquatic lifestyle, being parasites of marine and freshwater plants, animals.
3. Zygomycetes are typical unicellular fungi, in some representatives of the mycelium with several weak septa. Representatives: mucor, trichomycetes, spinellus, zoopagalis and others. Among them there are soil inhabitants and parasites of humans, animals and plants.
4. Ascomycetes are most multicellular, but unicellular fungi are also found. Examples: yeast, morels, truffles, lines, parmelia and others. They got their name for the structural features of the spores, which are called ascospores. Some representatives lose their ability to reproduce during their life and are attributed to deuteromycetes, that is, imperfect fungi.

Each department has its own characteristics and characteristics, and even the species are all the more diverse. An interesting way of life, important economic value. In addition, fungi play an important ecological role in nature.

Features of the structure and lifestyle

Before answering the question: "Describe the role of unicellular fungi in nature," you should consider their structural features and lifestyle. After all, it will depend on this exactly what significance they will have for surrounding organisms, including for humans.

So, the structural features of unicellular mushrooms.

1. Mycelium is either not developed at all or very weak. It can be multicore or represented by a single cell with one nucleus.
2. Reproduction is often asexual, although the sexual process is also characteristic of many.
3. Zoospores (hitridiomycota) are formed in water representatives, which freely move in water with the help of flagella. Ascomycetes have special sporulation organs of the bag in which ascospores ripen. Their number does not exceed eight pieces.
4. Some soil zygomycetes form mycorrhiza with tree roots.
5. Imperfect mushrooms come into symbiosis with bacteria, forming a useful Kombucha.

In general, the structure of almost all fungi, as well as the internal cellular composition, is almost identical. And it doesn’t matter whether he is superior or imperfect. Therefore, the classification is always based on the main feature - the method of reproduction.

Lifestyle Features:

1. The vast majority are obligate or facultative parasites.
2. Many have adapted to life in water or soil.
3. Some representatives release a large number of enzymes into the environment in order to prepare food for themselves. Even without a branched mycelium, some organisms release thin rhizoids, which are attached to the substrate and capture (absorb) food.
4. Among zygomycetes there are special representatives - zoopagalis. They got their name for a predatory lifestyle. They capture with sticky hyphae the larvae of insects, nematodes and other protozoa and eat them, digesting from the outside.
5. In the process of life, many representatives (especially yeast) are able to produce valuable medicinal substances, enzymes, important chemical compounds.

It is difficult to identify common features for all in the way of life, because the number of species is too large. Therefore, it is better to dwell in more detail on the most frequently encountered and important for humans.

Breeding process

We have already clarified that the main distinguishing feature of the organisms under consideration is a way of reproducing offspring. Reproduction of unicellular fungi can be carried out in three ways:

• sexual
• vegetative;
• asexual.

Consider all the options in more detail.

1. Asexual reproduction implies the formation of spores within special formations of sporangia. So, for example, in the Chytridiae these are mobile zoospores, and in Ascomycetes, ascospores of endogenous origin.
2. Vegetative for unicellular representatives involves budding. That is, one cell buds and becomes an independent organism. This happens in yeast, which are generally considered secondarily unicellular fungi.
3. The sexual process does not occur in different species. However, there are three possible options: heterogamy, oogamy and isogamy. In any case, the essence is the merger of germ cells with the formation of a zygote. Most often, it is covered with a dense shell and experiences a state of rest for some time. After this, the mycelium begins to form and a new organism grows. Even in the case of multicellular representatives, the existence of male and female parts is out of the question. They simply talk about the presence of "+" and "-" sides of the mycelium, which merge to form a dicarion.

Of course, there are features that help identify some representatives. However, the general patterns of reproduction of unicellular fungi are precisely those described above.

Penicillus and its characteristic

The fact that penicillus is a unicellular mushroom cannot be said. The thing is that it belongs to the class of mold representatives, most of which are the simplest in organization. Therefore, he is often credited with similar features. However, penicillus, as well as his close friend, aspergillus, is the owner of a multicellular branching mycelium.

This mushroom was discovered by Ernest Duchenne in 1897. It was he who first drew attention to how in Arabia an incomprehensible greenish coating was used to heal the wounds of horses. After examining its structure, the young man (and Duchenne was only 23 years old) came to the conclusion that this organism is a fungus that has antibacterial properties, as it is able to destroy colic eicherichia - one of the most pathogenic and harmful bacteria.

For a long time no one listened to its discovery. In 1949, Fleming proved the antiseptic and antibacterial properties of this fungus, and Duchenne's merit was recognized, though after the death of the latter.

The main component that is used to make penicillin medicine is an antibiotic produced during the life of the body.

Mold mushrooms

If you answer the question: "Describe the role of unicellular fungi in nature," then we can not say about other mold representatives. After all, most of them settle on the soil, giving it a grayish or bluish tint in the form of plaque. In this case, the decomposition of dead organics occurs. Therefore, in nature, these mushrooms play the role of a kind of orderlies.

The following representatives are very important for a person:

• aspergillus;
• penicillium;
• "noble rot";
• "noble mold."

All of them are active participants in the process of preparing rare and tasty cheeses, wines, food additives, antibiotics and other valuable substances.

Mukor

The most typical representative of the considered organisms is mucor. A unicellular fungus that has a sufficiently large, branching mycelium, while formed by only one cell. There are no partitions in it. It belongs to the mold fungi of the zygomycetes department.

It is difficult to call this mushroom useful, because its main merit is spoilage of products and the formation of numerous mucoromycosis. However, some species are still used by man to make "Chinese yeast." This is a special sourdough serving for the preparation of certain foods. For example, soy cheese. Some types of mucor are a source of enzymes and antibiotics.

On the soil and products of the colony of these fungi form a fluffy coating of beige and gray, clearly visible to the naked eye.

Yeast

One-celled fungi include a representative such as yeast. However, these organisms should be considered secondarily unicellular, since they live in multi-budding colonies. The mycelium of each representative is unicellular, without partitions. But close cohabitation of several forms at once makes us think of multicellularity.

In general, yeast is a very useful mushroom. Not all, of course, but many of them. So, since ancient times, man used them for baking bread, making wine and brewing. Even 6 thousand years ago BC. e. these creatures were used everywhere in Egypt.

Bread was baked using the remains of the old yeast. This led to the degeneration of the culture, it became completely genetically pure and homogeneous. Therefore, today there are such "breeds" of yeast that were not created by evolution in nature, but were the result of human activities.

An interesting feature of yeast is that they are facultative parasites. That is, in the presence of oxygen they breathe freely, releasing carbon dioxide. But even under anaerobic conditions, they do not disappear, oxidizing sugars (fermentation).

Different types of yeast are able to process a different substrate. Some can ferment only simple sugars, hexoses. But there are those that process not only carbohydrates, but also proteins, lipids, carboxylic acids.

The products that are released as a result of the vital activity of these fungi are important to humans. Namely:

• diacetyl;
• isoamyl alcohol;
• fusel oils;
• dimethyl sulfide and others.

The combination of these substances determines the quality of the products. This directly affects its organoleptic properties.

Parasitic unicellular representatives of fungi

Among parasites, the most dangerous unicellular are those that cause mycoses in humans and animals, as well as various molds and rot in plants.

1. Trichophyton and microsporum are two species that cause serious skin diseases in humans.
2. Mushrooms of the genus Candida - cause candidiasis disease.
3. Dermatophytes are fungi that cause nail plate disease - onychomycosis.
4. Piedra, exophila, malasis - cause various lichens on parts of the body.
5. The black hairy fungus causes a disease that manifests itself in black on the tongue of humans and animals.
6. Phytophthora is a dangerous fungus that infects plants and causes the formation of black rot on the roots and leaves.

And this is still an incomplete list of those representatives that are pathogenic, harmful and extremely dangerous to health and harvest.

The role of unicellular fungi in nature

If you are faced with the task of such a plan: "Describe the role of unicellular mushrooms," then in the first place, all the pluses should be identified. We mentioned a lot about them:

• used in the chemical industry;
• in food;
• serve for the preparation of agricultural feed;
• are natural decomposers of organics, that is, orderlies and so on.

But also we should not forget about the minuses, which are also many. Indeed, most unicellular fungi are parasitic organisms.