Hormonal function. The metabolism in an organism is regulated by various mechanisms. In this regulation the important place is taken by the hormones developed in endocrine glands. A number of hormones is presented by proteins or polypeptides, for example hormones of a hypophysis, pancreas, etc.
The following important property is that enzymes are in fabrics and cages in an inactive form (pro-enzyme. Its classical examples are inactive forms of pepsin and trypsin. Existence of inactive forms of enzymes has great biological value. If pepsin was developed at once in an active form, pepsin "digested" a stomach wall, i.e. the stomach would "digest" itself.
At compound of two or several amino acids more difficult connection - polypeptide is formed. Polypeptides, connecting, form even more complex and large particles and as a result - a difficult molecule of protein.
Polymeric molecule of protein at connection in a long of beads amino acids. They on a thread of chemical bonds thanks to the available for all amino-and carboxyl attached to atom of an.
Glycoproteins. The Prostetichesky group is presented by carbohydrates and their derivatives. Have functions: structural and mechanical (are available in skin, a cartilage, sinews); catalytic (enzymes); the protective; participation in regulation of cellular division.
The return process is the renaturation, that is restoration of physical and chemical and biological properties of protein. Sometimes for this purpose it is enough to remove denaturant object. Renaturation is impossible if primary structure is mentioned.
In different editions two concepts are applied: "enzymes" and "enzymes". These names are identical. They designate one and too - biological catalysts. The first word is translated as "ferment", the second - "in yeast".
Represents a linear chain of amino acids (a polipepta, located in a certain sequence with the accurate genetically caused order of alternation and connected among themselves by peptide communications.
Metalproteins. Contain cations of one or several metals. Most often it is iron, copper, zinc, molybdenum, manganese, nickel is more rare. The proteinaceous component is connected with metal coordination communication.
Nutritious (reserve) function. This function is carried out by the so-called reserve proteins which are power supplies for development of a fruit, for example proteins of egg (ovalbumina). The main protein of milk (casein) also carries out mainly nutritious function. Some other proteins is undoubtedly used in an organism as a source of amino acids which in turn are predecessors of biologically active agents regulating processes of a metabolism.
At the majority of proteins the spatial organization comes to an end with tertiary structure, but for some proteins with a molecular weight more than 50-100 thousand constructed from some polypeptide chains the quarternary is characteristic.
It is possible to call still some vital functions of proteins, in particular ability to keep onkotichesky pressure in cages and blood, the buffer properties maintaining physiological value the internal environment, etc.