嗜热氢氧化细菌施氏芽孢杆菌中一种七铁铁氧化还原蛋白的纯化与特性分析

Purification and characterization of a 7Fe ferredoxin from a thermophilic hydrogen-oxidizing bacterium, Bacillus schlegelii.

作者信息

Aono S, Kurita H, Uno S, Okura I

机构信息

Department of Bioengineering, Tokyo Institute of Technology, Kanagawa.

出版信息

J Biochem. 1992 Dec;112(6):792-5. doi: 10.1093/oxfordjournals.jbchem.a123977.

DOI:10.1093/oxfordjournals.jbchem.a123977

PMID:1338329

Abstract

A ferredoxin (Fd) was purified from a thermophilic hydrogen-oxidizing bacterium, Bacillus schlegelii. This ferredoxin was a monomer with apparent molecular weight of 13,000 and contained 7 mol Fe/mol ferredoxin. The oxidized ferredoxin showed the characteristic EPR spectrum for [3Fe-4S]1+ (1.2 spin/mol Fd). This signal disappeared upon reduction with dithionite and new signals due to [3Fe-4S]0 and [4Fe-4S]1+ (0.7 spin/mol Fd) appeared. The quantitation of EPR signals and the iron content reveal that B. schlegelii ferredoxin contains one [3Fe-4S]1+/0 and one [4Fe-4S]2+/1+ cluster. The ferredoxin has the characteristic distribution of cysteines (-Cys8-X7-Cys16-X3-Cys20-Pro-) for 7Fe ferredoxins in the N-terminus.

摘要

从嗜热氢氧化细菌施氏芽孢杆菌（Bacillus schlegelii）中纯化出一种铁氧化还原蛋白（ferredoxin，Fd）。这种铁氧化还原蛋白是一种单体，表观分子量为13,000，每摩尔铁氧化还原蛋白含有7摩尔铁。氧化态的铁氧化还原蛋白显示出[3Fe-4S]1+的特征电子顺磁共振（EPR）谱（每摩尔Fd有1.2个自旋）。用连二亚硫酸盐还原后，该信号消失，同时出现了由于[3Fe-4S]0和[4Fe-4S]1+（每摩尔Fd有0.7个自旋）产生的新信号。EPR信号的定量分析和铁含量表明，施氏芽孢杆菌铁氧化还原蛋白含有一个[3Fe-4S]1+/0簇和一个[4Fe-4S]2+/1+簇。该铁氧化还原蛋白在N端具有7Fe铁氧化还原蛋白特有的半胱氨酸分布（-Cys8-X7-Cys16-X3-Cys20-Pro-）。