Introduction
Enzymes are so-called biocatalysts, without whose intervention no regulated and efficient metabolism could take place. They can often be recognized by the suffix -ase, which indicates that the substance in question is an enzyme. In some cases, however, enzymes also have randomly chosen or historically determined names which do not allow any conclusions to be drawn.
They are divided into six main classes according to the chemical reaction they catalyse. Enzymes are involved in metabolic processes in the cell, i.e. energy production, energy release, conversion processes and substrate conversions. But they also play a decisive role in digestion.
What enzymes are there?
In view of the fact that enzymes are involved in every chemical reaction in metabolism, in digestion and also in the multiplication of genetic information, it is hardly surprising that over 2000 different enzymes are known to date alone. In the course of current and future research, one or the other enzyme will probably be added. Biocatalysts are divided into six main classes and a large number of subclasses.
An enzyme is classified and named according to the type of chemical reaction in which it is involved. Some enzymes can also be assigned to more than one class because they support not just one but several similar reactions. Oxidoreductases, transferases, hydrolases, lyases, isomerases and ligases are distinguished.
In addition, they can be classified according to their structure and the additional substances they need for their function. Some enzymes are so-called pure protein enzymes. They do not need any additional substances and can catalyse the reaction on their own. Others, on the other hand, need cofactors and coenzymes that bind to them temporarily or permanently and help to carry out the reaction. The latter are also known as holoenzymes, made up of the actual enzyme (apoenzyme) and the coenzyme or substrate.
General tasks
Enzymes are biological catalysts, in short also called biocatalysts. A catalyst is a substance that is able to reduce the so-called activation energy of a reaction. Colloquially, this means that a chemical reaction requires less energy to start and run.
In addition, the use of catalysts means that a reaction can run faster. Without enzymes, the human metabolism would therefore be far less rapid and, above all, effective. Without enzymes, the human being could not exist in the form in which we do.
Enzymes are usually proteins, i.e. proteins. Only a few of the enzymes involved in genetic reproduction are so-called ribozymes and are made up of RNA strands. By definition, catalysts are not altered or consumed by their use.
This means that one enzyme can catalyse a large number of reactions in succession. This in turn saves the organism further energy that does not have to be used for the new formation of enzymes. In addition, enzymes are reaction-specific, which means that they cannot catalyse every single reaction.
They are precisely matched to the substances of a reaction. In this way, their efficiency is increased. In general, enzymes are involved in the transfer of chemical groups between two different substances, the conversion, as well as the formation and degradation of individual substances.
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