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Peptides and Polypeptides Information and Facts


At the most simplistic level, peptides are strings or chains, of two or more amino acids that have bonded together. What are amino acids? Amino acids are organic compounds made up of amine and carboxyl compounds necessary for life. These compounds are characterized by the presence of oxygen, hydrogen, carbon and nitrogen. An amine compound located at the end of a peptide chain is called? Its called the N-terminus, and it is situated at the left end of a horizontal peptide chemical diagram. What is a carboxyl compound located at the end of the chain called? It is called the C-terminus, and it is situated on the right side of a peptide chemical diagram. What is a protein? They are peptides comprising greater than 10 amino acids. Polypeptides are large proteins distinguished from peptides primarily in terms of molecular weight. Polypeptides have a molecular weight in the tens of thousands while peptides weigh only in the thousands. In the nutritional sense, peptides are the result of nourishment broken down through the action of enzymes prior to absorption into the bloodstream.

As individual combinations of specific amino acids, individual peptides have a particular function. The reason for this has mainly to do with peptide chains ending in two amine compounds, two carboxyl compounds or a carboxyl at one end and an amine at the other. Peptides are, consequently, constrained to the extent that they may bond and interact with other structures. Though unable to change shape, peptides may rotate in order to bond appropriately to surrounding compounds. The rigid shape of peptides also affects how they are digested in living organisms. Cellulose, instead, becomes processed as waste, playing an important role in human digestive regularity. In this respect, with a proper diet, peptides are the ingredients necessary for the production of energy in the body.

What are polypeptides

In contrast to peptides, polypeptides function as hormones that trigger specific physiological processes. In humans, hormone secretions of polypeptides occur in the endocrine system through a series of glands distributed throughout the body. Hormones are released in response to specific stimuli received by the brain. The brain subsequently triggers the appropriate endocrine gland to release the hormones necessary for the necessary physiological response. Upon release of a hormone, the constituent polypeptides enter the bloodstream in order to initiate a function in a specific part of the body. Adrenaline is a common example of such a hormone, released to provide energy in response to certain situations, such as emergencies.

What shape are polypeptides?

As an essentially fluid form, polypeptides are not dimensionally limited in the same way as regular peptides. As proteins, peptides assume a very specific shape, and this shape dictates their physiological role based on how they are able to interact and bond with other molecules. The physical shape assumed by a polypeptide is determined by the molecules by which it is surrounded. Just as peptides serve to nourish and replenish nutrients in the body, polypeptides activate specific functions. The polypeptide glutathione, for instance, is a basic component of living cells necessary for the physiological growth. The polypeptide somatostatin, by contrast, prevents such growth by inhibiting those hormones which accompany peptides such as glutathione. For this reason, somatostatin has been used to slow the effect of ulcers. Insulin is among the most commonly recognized polypeptides because of its role in the digestion of sugars and use in diabetic treatment. To this extent, peptides and polypeptides may behave as antioxidants and neurotransmitters as well as cofactors in the natural effectiveness of enzymes.