Spectroscopic studies on the mode of binding of ATP, UTP and α‐amanitin with yeast RNA polymerase II

FEBS Letters

Chatterji, Dipankar¹  Bhargava, Purnima¹ 

[1] Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007 (A.P.), India

关键词: Fluorescence;    NMR;    Substrate;    Inhibitor;    RNA polymerase II;    Binding constant;   

DOI  :  10.1016/0014-5793(88)81025-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The binding affinity between the substrates ATP and UTP with the purified yeast RNA polymerase II have been studied here in the presence and absence of Mn²⁺. In the absence of template DNA, both ATP and UTP showed tight binding with the enzyme without preference for any specific nucleotide, unlike Escherichia coli RNA polymerase. Fluorescence titration of the tryptophan emission of the enzyme by nucleoside triphosphate substrates gave an estimated K _d value around 65 μM in the absence of Mn²⁺ whereas in the presence of Mn²⁺, the K _d was 20 μM. The effect of substrates on the longitudinal relaxation of the HDO proton in enzyme-substrate complex also yielded a similar K _d value.

【 授权许可】

Unknown