This Article Full Text (PDF) A correction has been published Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Dietrichs, D Articles by Andreesen, J R Search for Related Content PubMed PubMed Citation Articles by Dietrichs, D Articles by Andreesen, J R

research-article

Interaction of selenoprotein PA and the thioredoxin system, components of the NADPH-dependent reduction of glycine in Eubacterium acidaminophilum and Clostridium litorale [corrected]

Institut für Mikrobiologie der Universität, Göttingen, Germany.

ABSTRACT

Purification of protein PA of the glycine reductase complex from Eubacterium acidaminophilum and Clostridium litorale [corrected] was monitored by a new spectrophotometric assay. The procedure depended on a specific two- to threefold stimulation of a dihydrolipoamide dehydrogenase activity that is elicited by the interaction of a thioredoxin reductase-like flavoprotein and thioredoxin from both organisms. Protein PA isolated from E. acidaminophilum by 75Se labeling and monitoring of the dithioerythritol-dependent glycine reductase activity was identical in its biochemical, structural, and immunological properties to the protein isolated by using the stimulation assay. Proteins PA from both organisms were glycoproteins of Mr about 18,500 and exhibited very similar N-terminal amino acid sequences. Depletion of thioredoxin from crude extracts of E. acidaminophilum totally diminished the NADPH-dependent but not the dithioerythritol-dependent glycine reduction. The former activity could be fully restored by adding thioredoxin. Antibodies raised against the thioredoxin reductase-like flavoprotein or thioredoxin inhibited to a high extent NADPH-dependent but not dithioerythritol-dependent glycine reductase activity. These results indicate the involvement of the thioredoxin system in the electron flow from reduced pyridine nucleotides to glycine reductase.

This article has been cited by other articles:

• Kabisch, U. C., Grantzdorffer, A., Schierhorn, A., Rucknagel, K. P., Andreesen, J. R., Pich, A. (1999). Identification of D-Proline Reductase from Clostridium sticklandii as a Selenoenzyme and Indications for a Catalytically Active Pyruvoyl Group Derived from a Cysteine Residue by Cleavage of a Proprotein. J. Biol. Chem. 274: 8445-8454 [Abstract] [Full Text]  
• Croteau, W., Bodwell, J. E., Richardson, J. M., Germain, D. L. St. (1998). Conserved Cysteines in the Type 1 Deiodinase Selenoprotein Are Not Essential for Catalytic Activity. J. Biol. Chem. 273: 25230-25236 [Abstract] [Full Text]