Classes of Enzymes

The enzymes are responsible for the first stage of the metabolic process, which involves reacting with a molecule known as the substrate in order to produce energy. Enzymes are molecules that transform substrates into other different molecules, which are referred to as products.

Because of their importance in the maintenance of life processes, the regulation of enzymes has long been recognised as a critical component of clinical diagnosis. With the exception of the ribozymes, which are a class of RNA catalysts, all enzymes contain protein as their macromolecular constituents. Because of the ribonucleic acid enzyme in its name, the term “ribozyme” was coined. There are many types of ribozymes, which are ribonucleic acid molecules that catalyse processes in one of their own bonds or between other RNAs.

It is possible to find enzymes in all of the tissues and fluids of the body. Almost all of the reactions that take place in metabolic pathways are catalysed by enzymes that reside within the cell. The catalysis in cells is governed by enzymes in the plasma membrane in response to cellular signals, while the clotting of blood is governed by enzymes in the circulation. The functions of enzymes are at the heart of the majority of life’s most important processes.

The Structure of an Enzyme

Enzymes are made up of a linear chain of amino acids that combine to form a three-dimensional structure when heated. The structure of an enzyme is determined by the amino acid sequence, which in turn is determined by the catalytic activity of the enzyme. When heated, the structure of the enzyme denatures, resulting in a reduction in enzyme activity, which is often correlated with increased temperature.

The size of enzymes is often large in comparison to their substrates, with sizes ranging from 62 amino acid residues in the case of a protein to an average of 2500 residues in the case of fatty acid synthase. During catalysis, just a small part of the structure is engaged, and it is located close to one of the binding sites. The active site of an enzyme is formed by the catalytic site and the binding site working together. There are only a few ribozymes in existence, and they function as RNA-based biological catalysts. It reacts with proteins only when they are in complex.

The Classification of Enzymes

Previously, enzymes were given names depending on the person who discovered the enzyme. The classification system got more comprehensive as additional study was conducted.

According to the International Union of Biochemists (I U B), enzymes are classified into six functional classes based on the kind of reaction that they are used to catalyse and are further subdivided into subclasses based on the type of reaction that they are used to catalyse. Hydrolases, oxidoreductases, lyases, transferases, ligases, and isomerases are among the six types of enzymes that exist.

Oxidoreductases

In the body, these enzymes catalyse oxidation and reduction reactions, for example, the oxidation of pyruvate to acetyl coenzyme A, which occurs in the presence of pyruvate dehydrogenase.

Transferases

These are catalysts that aid in the transfer of chemical groups from one substance to another. One such enzyme is a transaminase, which is responsible for the transfer of an amino group from one molecule to another.

Hydrolases

They are responsible for the hydrolysis of a bond. Pepsin, for example, is an enzyme that hydrolyzes peptide bonds found in proteins.

Lyases

For example, aldolase (an enzyme in glycolysis) catalyses the breaking of fructose-1, 6-bisphosphate into glyceraldehyde-3-phosphate and dihydroxyacetone phosphate without requiring the use of a catalytic agent.

Isomerases

They aid in the creation of an isomer of a molecule by catalysing the reaction. In glycogenolysis, for example, phosphoglucomutase catalyses the conversion of glucose-1-phosphate to glucose-6-phosphate (in which the phosphate group is moved from one position in the same component to another position in the same compound) (glycogen is converted to glucose for energy to be released quickly).

Ligases

Ligases are enzymes that catalyse the joining of two molecules. For example, DNA ligase is a protein that catalyses the joining of two DNA segments by establishing a phosphodiester bond between them.

Cofactors

Cofactors are non-proteinous molecules that interact with enzymes and aid in their function. An enzyme’s ability to function is dependent on the presence of a cofactor. Apoenzymes are enzymes that do not require the presence of a cofactor. The holoenzyme is made up of an enzyme and a cofactor that work together.

Enzymes applications

The following are some instances of enzymes in action:

Beverages

The characteristics of alcoholic beverages produced by fermentation are highly variable and depend on a variety of circumstances. The fermented product differs depending on the type of plant product that is being used as well as the type of enzyme that is being employed.

Grapes, honey, hops, wheat, cassava roots, and potatoes are examples of crops that can be grown depending on the ingredients available. Plant fermentation is used to create beverages such as beer, wine, and other alcoholic beverages.

Products pertaining to food

In our everyday lives, bread can be considered to be the most excellent example of fermentation.

In order to make bread, a small amount of yeast and sugar is put into the batter. The bread will then puff up as a result of the fermentation of the sugar by the enzyme action in the yeast, which will result in the generation of carbon dioxide gas throughout the baking process. The texture of the bread is provided by this process, which would be absent if the fermentation process were not carried out during the baking phase.

The Effects of the Drug

Inhibition or stimulation of enzyme activity can be achieved through the administration of medicines that tend to act in close proximity to the enzyme’s active site.

Enzymes Functions

Enzymes are responsible for a variety of processes in our bodies. These are some examples:

1.Enzymes play a role in the transmission of signals. The protein kinase enzyme, which catalyses the phosphorylation of proteins, is the most often seen enzyme in the process.

They do this by breaking down huge molecules into smaller compounds that can be more easily absorbed by the human body.

2.They contribute to the production of energy in the body. ATP synthase is an enzyme that is involved in the production of energy from carbohydrates.

3.When ions migrate through the plasma membrane, it is because of the action of enzymes.

Enzymes are involved in a variety of biochemical activities, such as oxidation, reduction, hydrolysis, and others, that help the body eliminate non-nutritive substances from the body.

They have the ability to remodel the internal structure of the cell, which allows them to regulate cellular functions.

Conclusion

Concentration and Type of Substrate Enzymes have a saturation point, which means that after all of the enzymes that have been added have been occupied by the substrate molecules, the enzyme’s activity will halt. Immediately after the reaction begins, the rate at which the enzyme acts increases with each additional addition of substrate. However, at a saturation threshold where the quantity of substrate molecules outnumbers the number of free enzyme molecules, the velocity remains constant.

Another aspect that influences the enzyme’s activity is the type of substrate used. The molecules that bind to the enzyme’s active site have the potential to impede the enzyme’s function, and this type of substrate is referred to as an inhibitor. Biologically active competitive inhibitors are compounds that compete with a specific substrate for the active site of an enzyme. They have a structure that is similar to the specific substrate of the enzyme, and they attach to the enzyme, preventing it from performing its enzymatic action. This idea is utilised in the treatment of bacterial infectious illnesses.