Fungi, with some very rare exceptions, are not transmitters of pathologies, but rather are the causes of some diseases, which affect humans and also animals and other living beings such as plants. Fungi are a very large family of organisms that sometimes look like plants, but which, genetically, are much closer to animals.
When some fungi cause diseases, it is normally in individuals who are immunocompromised, that is, they have a weak immune system: these are known as opportunists. Fungi are in the environment, usually in the form of spores. We breathe them daily and they are part of our microbiota and the microorganisms that are naturally on our skin. What happens in organisms that have a weak immune system is that fungi grow and reproduce much faster than normal. That is why they can cause pathologies.
There are some milder ones, for example related to the skin, caused by the so-called dermatophytes, which cause ringworm (very well known in animals and humans), athlete's foot or even dandruff (which is so common). But they can also cause more serious diseases, such as lung pathologies due to inhalation of the spores; among them is aspergillosis, caused by a fungus of the genus Aspergillus, and that can lead to a very serious infection. Another serious lung disease caused by fungi is mucormycosis, which currently has a high incidence worldwide, especially in India. And there are other very common ones, also caused by fungi of the genus Candidawhich are candidiasis, the most common cause of vaginal infections.
Fungi are also very relevant in agriculture because they can infect plants and vegetable crops in various ways: their leaves, their fruits and even their roots. And these infections can cause the collapse of plants and crops. There are some very virulent ones that are causing a lot of losses around the world. For example, in the field of citrus farming, some of the genus Penicillium They cause rot in oranges, tangerines, grapefruits, lemons, etc. Another significant example is the rice plant, the crop par excellence worldwide, which is highly affected by a fungus of the genus Magnaporthewhich also generates many losses throughout the world.
The problem that exists now with fungi that cause plant diseases is that we are running out of enough fungicides to deal with this problem. There are very few antifungals, they have been used for a long time and fungi are beginning to show resistance to them. Exactly the same thing happens in humans. Those that exist are beginning to stop working, since, just as is happening with bacteria and antibiotics, fungi have developed resistance that makes antifungal medications not as effective, or even stop being effective completely. For this reason, at this time, research on fungi and the development of new antifungals is very important.
Medicinal, tasty and industrial mushrooms
There are several types of fungi in nature, and not all of them cause diseases. In fact, many of them are used in food production or are used for the production of compounds of industrial interest. The simplest, yeasts, are unicellular, composed of a single cell. We know them above all because they are responsible, for example, for the fermentation of bread dough, or for alcoholic fermentation, used to make beers, wines or ciders. Then there are filamentous fungi, composed of more cells, they are multicellular. They are easily recognized by presenting those hairs (the so-called mycelium), which we can see in our daily lives. These are very interesting because among them are those of the genus Penicillium either Aspergillusfrom which antibiotics have been obtained (such as penicillin) or that are used in the production of foods such as cheeses and sausages, or also in the production of preservatives such as citric acid.
And finally there are macroscopic fungi, which are those that can be seen with the naked eye and which we call mushrooms. Many are edible, others are toxic, and still others are hallucinogenic because they contain compounds that cause hallucinations. Fungi feed mostly on organic matter, often from waste. And this makes them very interesting for the circular economy, since they are capable of growing on waste—agricultural, forestry or even household waste—, being nourished by it and producing other types of usable compounds. This is a potential that fungi have and is one of the lines of research of our laboratory: fungi that act as biofactories, in which products of interest for different industries are obtained from waste.
Sandra Garrigues Cubells She has a doctorate in biotechnology, a researcher at the Institute of Agrochemistry and Food Technology (IATA-CSIC).
Question sent via email byJulio Chacel García
Coordination and writing:Victoria Toro
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