Redox regulation of 3'-phosphoadenylylsulfate reductase from Escherichia coli by glutathione and glutaredoxins |
| |
Authors: | Lillig Christopher Horst Potamitou Aristi Schwenn Jens-Dirk Vlamis-Gardikas Alexios Holmgren Arne |
| |
Institution: | Medical Nobel Institute for Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Scheeles V?g 2, 17177 Stockholm, Sweden. |
| |
Abstract: | Inorganic sulfate (SO42-, S+VI) is reduced in vivo to sulfite (SO32-, S+IV) via phosphoadenylylsulfate (PAPS) reductase. Escherichia coli lacking glutathione reductase and glutaredoxins (gor-grxA-grxB-grxC-) barely grows on sulfate. We found that incubation of PAPS reductase with oxidized glutathione leads to enzyme inactivation with simultaneous formation of a mixed disulfide between glutathione and the active site Cys-239. A newly developed method based on thiol-specific fluorescent alkylation and gel electrophoresis showed that glutathionylated PAPS reductase is reduced by glutaredoxins via a monothiol mechanism. This glutathionylated species was also observed in poorly growing gor-grxA-grxB-grxC- cells expressing inactive glutaredoxin 2 (Grx2) C9S/C12S. However, it was absent in better growing cells expressing monothiol Grx2 C12S or wild type Grx2. Reversible glutathionylation may thus regulate the activity of PAPS reductase in vivo. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|