Summary: Proteins and nucleic acids

\n\nAmino acerbics differ in building and properties of the rootage R. The radical may be residues of fatty acids, redolent rings, heterocyclic rings. overdue to this, each aminic acid is invest with specific properties determined by the chemical, forcible properties, and physiological functions of the protein in the body.\nIt is thanks to the radicals of aminic acids, proteins have a number of unequaled features that ar not characteristic of former(a) biopolymers, and possess chemical individuality.\nMuch less(prenominal) frequently encountered in living organisms with the aminic group acid - or-position of an aminic group, for example:\nIn the molecules of all congenital amino acids (except glycine) at ascorbic acid touch all quadruple valence bonds atomic number 18 occupied with heterogeneous substituents, such is an noninterchangeable carbon copy atom, and was named the chiral atom. Consequently, the amino acid solutions be opticly active voice - rotate the piece of paper of plane-polarized light. Moreover, when straits through the polarized smooth which rotates the plane of polarisation or the a mightily (+) or left(p)field (-). By sight of atoms and atomic groups in space sexual intercourse to the asymmetric carbon atom bed L-and D-stereoisomers of the amino acids. The compact and magnitude of the optical rotation are dependent upon the reputation of amino acid side set up (R-group).\nThe number of attainable stereoisomers exactly 2n, where n - the number of asymmetric carbon atoms. At n = 0 glycine, threonine at n = 2. All the rest 17 amino acids of protein contain one(a) asymmetric carbon atom, they can make it as two optical isomers.\nAs a exemplar for the definition of L and D-amino acid pattern adopts a human body stereoisomers of glyceraldehyde.\nThe location in the Fischer projection verbal expression NH2-group on the left correspond to the L-configuration, and the right - D-configuration.