The polynucleotide double helix as a versatile assembly template during polymer biogenesis

Abstract

A hypothesis is put forward for consideration in which the ubiquitous duplex polynucleotide is given a widespread function in nature as a special kind of assembly template for the formation of all high polymers. It is envisaged as a means to an end rather than a final product, as distinct from either a metabolically active polymer such as an enzyme protein or a structurally necessary one such as cellulose for instance. In other words, its life is imagined to be essentially transitory. During its synthesis it simultaneously produces a variety of polymers depending on its fine structure format and on the nature of the polymer sub-units attached to the nucleotide monomer in the first instance. The latter in turn would depend on the nature of the substrate environment, the “activating” enzymes present, etc. The synthesis stage is imagined to take place in “ribosomal structures”; some of these would produce protein, some would be concerned with polysaccharide formation and others would synthesize polyisoprene, plant gums, etc. Indeed, the existence of “mixed” ribosomes producing mucopeptides such as the blood group substances could be just as readily imagined. The function would be mainly as an assembly “scaffolding” by which stereospecific morphological requirements could be met. The ancillary coding mechanism of polymer sub-units would require, in complex cases, additional interactions as in the instance of protein synthesis but the activation of these sub-units would be essentially similar for all polymers. It is emphasized that the theory is basically biogenetical in conception and does not seek to explain all mechanisms of limited ( in vitro) biosynthesis in the presence of primer molecules, although some of the available evidence on the matter comes, perforce, from these latter sources.