The Breath of fungi Varies depending on what type of fungus we are observing. In biology the fungi are known as Fungi , One of the kingdoms of nature where we can distinguish three large groups: molds, yeasts and mushrooms.
Fungi are eukaryotic organisms composed of cells with a well delimited nucleus and chitin walls. In addition, they are characterized because they are fed by absorption.
There are three large groups of fungi, yeasts, molds and mushrooms. Each type of fungus breathes in a certain way as seen below.
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Types of Breathing of Fungi
The cellular respiration or internal respiration, are a set of biochemical reactions by which certain organic compounds through the oxidation become inorganic substances that provide energy to the cell.
Within the fungi community we find two types of breathing: aerobic and anaerobic.
Aerobic respiration is one in which the final electron acceptor is the oxygen that will be reduced to water.
On the other hand we find the anaerobic respiration, which should not be confused with the fermentation, since in the latter there is no chain of electron transport. This breath is one in which the molecule used for the oxidation process is not oxygen.
Breath of fungi by their classification
To make the explanation of the types of respiration easier, we will classify them according to the types of fungi.
Yeasts
These types of fungi are characterized by being single-celled organisms, which means that they are only composed of one cell.
These organisms can survive without oxygen, but when oxygen is breathed anaerobically from other substances, they never take oxygen free.
Anaerobic respiration consists of extracting energy from a substance, used to oxidize glucose and thus obtaining adenosine triphosphate, also known as adenosine phosphate (hereafter ATP). This nucleodite is in charge of obtaining energy for the cell.
This type of breathing is also known as fermentation and the process that follows to obtain energy through the division of substances, is known as glycolysis.
In glycolysis the glucose molecule is decomposed into 6 carbons and a molecule of Pyruvic acid . And in this reaction two molecules of ATP are produced.
Yeasts also have a specific type of fermentation, which is known as alcoholic fermentation. By breaking down glucose molecules to obtain energy, ethanol is produced.
Fermentation is less effective than breathing as it takes less energy from the molecules. All possible substances that are used for the oxidation of glucose have less potential
Molds and mushrooms
These fungi are characterized by being multicellular fungi. This type of fungus has an aerobic respiration.
Breathing allows you to extract energy from organic molecules, especially glucose. In order to extract the ATP, it is necessary to oxidize the carbon, for that, oxygen is used from the air.
Oxygen passes through the plasma membranes and then the mitochondrial. In the latter it binds to electrons and hydrogen protons, forming water.
Stages of Breath of Fungi
To carry out the breathing process in the fungi is performed by stages or cycles.
Glucolysis
The first step is the glycolysis process. This is responsible for oxidizing glucose in order to obtain energy. There are ten enzymatic reactions that convert glucose into pyruvate molecules.
In the first phase of glycolysis, the glucose molecule is transformed into two glyceraldehyde molecules, using two ATPs. The use of two molecules of ATP in this phase, allows to duplicate the obtaining of energy in the following phase.
In the second phase, the glyceraldehyde obtained in the first phase is converted into a high energy compound. Through hydrolysis of this compound, an ATP molecule is generated.
Since we had obtained two molecules of glyceraldehyde in the first phase, we now have two ATPs. The coupling that occurs, forms two other molecules of pyruvate, so in this phase we finally get 4 molecules of ATP.
Krebs cycle
Once the glycolysis stage is over, we move on to the Krebs cycle or citric acid cycle. It is a metabolic route where a series of chemical reactions occurs that releases the energy produced in the oxidation process.
This is the part that carries out the oxidation of carbohydrates, fatty acids and amino acids to produce CO2, in order to release energy in a usable way for the cell.
Many of the enzymes are regulated by negative feedback, by allosteric ATP binding.
These enzymes include the pyruvate dehydrogenase complex which synthesizes the acetyl-CoA necessary for the first cycle reaction from pyruvate from glycolysis.
Also the enzymes citrate synthase, isocitrate dehydrogenase and α-ketoglutarate dehydrogenase, which catalyze the first three reactions of the Krebs cycle, are inhibited by high concentrations of ATP. This regulation slows down this degradative cycle when the energy level of the cell is good.
Some enzymes are also down regulated when the level of reducing power of the cell is high. Thus, the pyruvate dehydrogenase and citrate synthase complexes are regulated, among others.
Electron transport chain
Once the Krebs cycle is over, the cells of the fungi have a number of electron mechanisms that are in the plasmatic membrane , Which by means of reduction-oxidation reactions produce ATP cells.
The mission of this chain is to create an electrochemical gradient transport chain that is used to synthesize the ATP.
Cells that have the electron transport chain to synthesize ATP, without the need to use solar energy as a source of energy, are known as chemoprophs.
They can use inorganic compounds as substrates to obtain energy that will be used in respiratory metabolism.
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