5'-磷酸吡哆醛对人乙型肝炎病毒DNA聚合酶的灭活作用。

Inactivation of human hepatitis B virus DNA polymerase by pyridoxal 5'-phosphate.

作者信息

Oh S H, Park Y H, Woo K

机构信息

Department of Biochemistry, College of Medicine, Yonsei University, Seoul, Korea.

出版信息

J Med Virol. 1989 May;28(1):42-6. doi: 10.1002/jmv.1890280110.

DOI:10.1002/jmv.1890280110

PMID:2723616

Abstract

Human hepatitis B virus (HBV) DNA polymerase activity was inhibited by pyridoxal 5'-phosphate (PLP) specifically and noncompetitively with respect to deoxythymidine triphosphate (DTTP). NaBH4 reduction of PLP-HBV core proteins resulted in the complete inactivation of HBV DNA polymerase, and PLP modification of the enzyme was though to be mediated through Schiff-base formation. HBV DNA polymerase has a Michaelis constant (Km) of 0.31 microM for dTTP and an apparent inhibition constant (Ki) of 0.2 mM for PLP. Its inactivation and modification by PLP may be useful in the study of not only the reaction mechanism of catalysis, but also the physicochemical nature of the enzyme.

摘要

5'-磷酸吡哆醛（PLP）对人乙型肝炎病毒（HBV）DNA聚合酶活性具有特异性抑制作用，且对三磷酸脱氧胸苷（DTTP）呈非竞争性抑制。用硼氢化钠还原PLP-HBV核心蛋白可导致HBV DNA聚合酶完全失活，酶的PLP修饰被认为是通过席夫碱形成介导的。HBV DNA聚合酶对dTTP的米氏常数（Km）为0.31微摩尔，对PLP的表观抑制常数（Ki）为0.2毫摩尔。PLP对其的失活和修饰不仅可能有助于研究催化反应机制，还可能有助于研究该酶的物理化学性质。