Nucleoside und Nucleotide. Teil 16. Verhalten von 1‐(2′‐Desoxy‐β‐D‐ribofuranosyl)‐2(1 H)‐pyrimidinon‐5′‐triphosphat, 1‐(2′‐Desoxy‐β‐D‐ribofuranosyl)‐2(1 H)pyridinon‐5′‐triphosphat und 4‐Amino‐1‐(2′‐Desoxy‐β‐D‐ribofuranosyl)‐2(1 H)‐pyridinon‐5′‐triphosphat gegenüber DNA‐Polymerase

Abstract

Nucleosides and Nucleotides. Part 16. The Behaviour of 1‐(2′‐Deoxy‐β‐D‐ribofuranosyl)‐2(1H)‐pyrimidinone‐5′‐triphosphate, 1‐(2′‐Deoxy‐β‐D‐ribofuranosyl‐2(1H))‐pyridinone‐5′‐triphosphate and 4‐Amino‐1‐(2′‐desoxy‐β‐D‐ribofuranosyl)‐2(1H)‐pyridinone‐5′‐triphosphate towards DNA PolymeraseThe behaviour of nucleotide base analogs in the DNA synthesis in vitro was studied. The investigated nucleoside‐5′‐triphosphates 1‐(2′‐deoxy‐β‐D‐ribofuranosyl)‐2(1 H)‐pyrimidinone‐5′‐triphosphate (pppMd), 1‐(2′‐deoxy‐β‐D‐ribofuranosyl)‐2(1 H)‐pyridinone‐5′‐triphosphate (pppIId) and 4‐amino‐1‐(2′‐deoxy‐β‐D‐ribofuranosyl)‐2(1 H)‐pyridinone‐5′‐triphosphate (pppZd) can be considered to be analogs of 2′‐deoxy‐cytidine‐5′‐triphosphate. However, their ability to undergo base pairing to the complementary guanine is decreased. When pppMd, pppIId or pppZd are substituted for pppCd in the enzymatic synthesis of DNA by DNA polymerase no incorporation of these analogs is observed. They exhibit only a weak inhibition of the DNA synthesis. The mode of the inhibition is uncompetitive which shows that these nucleotide analogs cannot serve as substrates for the DNA polymerase.