Defining Terms for the Nucleic Acids

Abstract

In structural chemistry, defining the terms used to describe the geometry of molecules is fundamental in understanding basic principles. This chapter explains the conventions and nomenclature which have been adopted for nucleotides and nucleic acids. Although in nucleic acid research, atom numbering schemes and abbreviations are those recommended by the Commissions of the International Union of Pure and Applied Chemistry (IUPAC) and of the International Union of Biochemistry (IUB) (12–14), definitions of interatomic bond distances, bond angles, and torsion angles were, and still are, complex because of competing and conflicting terminology (15–18). Recently, an IUPAC-IUB subcomission worked out standard definitions (19) which will be explained and used throughout the following text.