[Biopolymers and evolution]

Abstract

Biopolymers are usually studied being extracted from the whole system of a cell or of an organism. Some important features are lost during such a procedure. It is necessary to take into account the behavior of proteins and nucleic acids in metabolic networks and to investigate their evolution. The substitutions of amino-acids metabolic networks residues are biologically possible in the polypeptides and proteins if they do not influence their spatial structure and function. The correlations of the primary structure with these properties are degenerate. The protein can be treated as "an edited statistical copolymer" (Ptitsyn). In the process of "edition" an important role is played by the ions of transient metals. Nucleic acids possess similar properties. It can be shown that the deleterious mutations of proteins can be compensated by the changes of their amount, spatial and temporal characteristics of the synthesis. Not only the structure of the protein is important but also the exact answers of the questions: how much, when and where? The contemporary theory of evolution unites phylogeny and onthogeny. The directionality of evolution is determined both by natural selection and by the already existing structure of an organism. Hence many characters are not adaptive. This is valid also for the molecular level of the structure. Thus three independent groups of facts and suggestions are presented, which confirm the neutral theory of evolution (Kimura) and elucidate its physical meaning. The molecular evolution does not coincide with the biological evolution.