An O2-inducible rubrerythrin-like protein, rubperoxin, is functional as a H2O2 reductase in an obligatory anaerobe Clostridium acetobutylicum
- 作者：Shinji Kawasaki ; Masaki Ono ; Yusuke Watamura ; Yu Sakai ; Takumi Satoh ; Toshiaki Arai ; Junichi Satoh ; Youichi Niimura
- 关键词：Rubrerythrin ; Rubperoxin ; Hydrogen peroxide ; Peroxidase ; Clostridium acetobutylicum
- 刊名：FEBS Letters
- 出版年：2007
- 期刊代码：70_00145793
- 类别：bio
- 出版时间：29 May 2007
- 卷：581
- 期：13
- 页码：2460-2464
- 文件大小：131 K
摘要
Clostridium acetobutylicum, an obligatory anaerobe, is able to grow microoxically with the accumulation of two functionally unknown O2-induced proteins identified by two-dimensional electrophoresis. One was determined to be a novel type rubrerythrin-like protein, named rubperoxin (Rpr) in this study, that conserves one rubredoxin-type Fe(SCys)4 site per polypeptide in the N-terminus. Recombinant rubperoxin expressed in E. coli purified in its oxidized form is a dimer with optical absorption maxima at 492, 377, and 277 nm. Reduced rubperoxin is rapidly and fully oxidized by a half molar ratio of H2O2 per mole protein, and slowly oxidized by t-butyl hydroperoxide and O2. Cell-free extracts from microoxically grown cells efficiently reduce rubperoxin when NAD(P)H is used as the electron donor (preferentially reduced by NADH). These results strongly suggest that rubperoxin is involved in NAD(P)H-dependent H2O2 detoxification in vivo.