Protective function of proteins. Structure and function of proteins

Proteins are the basis of all living organisms. It is these substances that act as a component of cell membranes, organelles, cartilage, tendons and horny skin derivatives. However, the protective function of proteins is one of the most important.

Proteins: Features of the structure

Along with lipids, carbohydrates and nucleic acids, proteins are organic substances that make up the basis of living things. All of them are natural biopolymers. These substances consist of repeatedly repeating structural units. They are called monomers. For proteins, such structural units are amino acids. Connecting in chains, they form a large macromolecule.

Levels of spatial organization of the protein

A chain of twenty amino acids can form different structures. These are the levels of spatial organization or conformation of the protein. The primary structure is represented by a chain of amino acids. When it spins into a spiral, a secondary one arises. Tertiary structure occurs when the previous conformation is twisted into a tangle or globule. But the following structure is the most complicated - Quaternary. It consists of several globules.

Properties of proteins

If the quaternary structure is destroyed before the primary, namely to the chain of amino acids, then there is a process called denaturation. He is reversible. A chain of amino acids can again form more complex structures. But when there is a destruction, i.e. Destruction of the primary structure, it is impossible to restore the protein . Such a process is irreversible. Destruction was carried out by each of us when thermally processed products consisting of protein - chicken eggs, fish, meat.

Protein functions: table

Protein molecules are very diverse. This causes a wide range of their capabilities, which are due to the structure of amino acids. The functions of proteins (the table contains the necessary information) are a necessary condition for the existence of living organisms.

Protective function of proteins in the body

As you can see, the functions of proteins are very diverse and important in their meaning. But we did not mention one more of them. The protective function of proteins in the body is to prevent the penetration of foreign substances that can cause significant harm to the body. If this happens, the specialized proteins can disarm them. These protectors are called antibodies or immunoglobulins.

The process of formation of immunity

With each sigh, pathogenic bacteria and viruses penetrate into our body. They fall into the blood, where they begin to multiply actively. However, on their way there is a significant barrier. These are blood plasma proteins - immunoglobulins or antibodies. They are specialized and are characterized by the ability to recognize and neutralize substances and structures alien to the body. They are called antigens. This is how the protective function of proteins manifests itself. Examples of it can be continued with information on interferon. This protein is also specialized and recognizes viruses. This substance is even the basis of many immunostimulatory drugs.

Thanks to the presence of protective proteins, the body is able to withstand disease-causing particles, i.e. At it the immunity is formed. He can be innate and acquired. The first all organisms are endowed since the birth, which is why life is possible. And acquired appears after the transfer of various infectious diseases.

Mechanical protection

Proteins perform a protective function, directly protecting cells and the entire body from mechanical influences. For example, the outer skeleton of crustaceans plays the role of shell, reliably protecting all the contents. Bones, muscles and cartilage form the basis of the body, and not only prevent damage to soft tissues and organs, but also ensure its movement in space.

Thrombus formation

The process of blood coagulation is also a protective function of proteins. It is possible due to the presence of specialized cells - platelets. If the blood vessels are damaged, they are destroyed. As a result, the soluble plasma protein fibrinogen is converted into its insoluble form - fibrin. This is a complex enzymatic process, as a result of which the filaments of fibrin very often intertwine and form a dense network that prevents the flow of blood. In other words, a blood clot or thrombus is formed. This is a protective reaction of the body. In normal life, this process lasts a maximum of ten minutes. But with the disease of blood incoagulability - hemophilia, which affects mostly men, a person can die even with a minor wound.

However, if blood clots form inside a blood vessel, it can be very dangerous. In some cases this even leads to a violation of its integrity and internal hemorrhage. In this case, drugs are recommended, on the contrary, blood thinning.

Chemical protection

The protective function of proteins is also manifested in the chemical control of pathogens. And it begins already in the oral cavity. Getting into it, food causes a reflex salivation. The basis of this substance is water, enzymes that break down polysaccharides and lysozyme. It is the latter substance that detoxifies harmful molecules, protecting the body from their further effects. It is found in the mucous membranes of the gastrointestinal tract, and in the tear fluid that washes the cornea of the eye. In large quantities, lysozyme is found in breast milk, nasopharyngeal mucus, and egg whites.

So, the protective function of proteins is manifested primarily in the neutralization of bacterial and viral particles in the blood of the body. As a result, he has the ability to resist disease-causing agents. It is called immunity. The proteins that make up the outer and inner skeleton protect the inner contents from mechanical damage. And protein substances, which are in saliva and other media, prevent the action of chemical agents on the body. In other words, the protective function of proteins is to provide the necessary conditions for all life processes.