铁型腈水合酶

Fe-type nitrile hydratase.

作者信息

Endo I, Nojiri M, Tsujimura M, Nakasako M, Nagashima S, Yohda M, Odaka M

机构信息

Biochemical Systems Laboratory, The Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama, Japan.

出版信息

J Inorg Biochem. 2001 Feb;83(4):247-53. doi: 10.1016/s0162-0134(00)00171-9.

DOI:10.1016/s0162-0134(00)00171-9

PMID:11293544

Abstract

The characteristic features of Fe-type nitrile hydratase (NHase) from Rhodococcus sp. N-771 are described. Through the biochemical analyses, we have found that nitric oxide (NO) regulates the photoreactivity of this enzyme by association with the non-heme iron center and photoinduced dissociation from it. The regulation is realized by a unique structure of the catalytic non-heme iron center composed of post-translationally modified cysteine-sulfinic (Cys-SO2H) and -sulfenic acids (Cys-SOH). To understand the biogenic mechanism and the functional role of these modifications, we constructed an over-expression system of whole NHase and individual subunits in Escherichia coli. The results of the studies on several recombinant NHases have shown that the Cys-SO2H oxidation of alphaC112 is indispensable for the catalytic activity of Fe-type NHase.

摘要

描述了来自红球菌属N-771的铁型腈水合酶（NHase）的特征。通过生化分析，我们发现一氧化氮（NO）通过与非血红素铁中心结合并从其光诱导解离来调节该酶的光反应性。这种调节是由催化性非血红素铁中心的独特结构实现的，该中心由翻译后修饰的半胱氨酸亚磺酸（Cys-SO2H）和亚磺酸（Cys-SOH）组成。为了理解这些修饰的生物发生机制和功能作用，我们在大肠杆菌中构建了完整NHase和单个亚基的过表达系统。对几种重组NHase的研究结果表明，αC112的Cys-SO2H氧化对于铁型NHase的催化活性是不可或缺的。