2F9S

2nd Crystal Structure Of A Soluble Domain Of ResA In The Oxidised Form

Summary for 2F9S

• Entry DOI: 10.2210/pdb2f9s/pdb
• Related: 1ST9 1SU9
• Descriptor: Thiol-disulfide oxidoreductase resA (2 entities in total)
• Functional Keywords: thioredoxin-like protein, oxidoreductase
• Biological source: Bacillus subtilis
• Cellular location: Cell membrane; Single-pass type II membrane protein: P35160
• Total number of polymer chains: 2
• Total formula weight: 34495.52

Authors

Colbert, C.L.,Wu, Q.,Erbel, P.J.A.,Gardner, K.H.,Deisenhofer, J. (deposition date: 2005-12-06, release date: 2006-04-18, Last modification date: 2024-10-09)

Primary citation

Colbert, C.L.,Wu, Q.,Erbel, P.J.A.,Gardner, K.H.,Deisenhofer, J.
Mechanism of substrate specificity in Bacillus subtilis ResA, a thioredoxin-like protein involved in cytochrome c maturation
Proc.Natl.Acad.Sci.USA, 103:4410-4415, 2006

PubMed Abstract: The covalent attachment of heme cofactors to the apo-polypeptides via thioether bonds is unique to the maturation of c-type cytochromes. A number of thiol-disulfide oxidoreductases prepare the apocytochrome for heme insertion in system I and II cytochrome c maturation. Although most thiol-disulfide oxidoreductases are nonspecific, the less common, specific thiol-disulfide oxidoreductases may be key to directing the usage of electrons. Here we demonstrate that unlike other thiol-disulfide oxidoreductases, the protein responsible for reducing oxidized apocytochrome c in Bacillus subtilis, ResA, is specific for cytochrome c550 and utilizes alternate conformations to recognize redox partners. We report solution NMR evidence that ResA undergoes a redox-dependent conformational change between oxidation states, as well as data showing that ResA utilizes a surface cavity present only in the reduced state to recognize a peptide derived from cytochrome c550. Finally, we confirm that ResA is a specific thiol-disulfide oxidoreductase by comparing its reactivity to our mimetic peptide with its reactivity to oxidized glutathione, a nonspecific substrate. This study biochemically demonstrates the specificity of this thiol-disulfide oxidoreductase and enables us to outline a structural mechanism of regulating the usage of electrons in a thiol-disulfide oxidoreductase system.

PubMed: 16537372
DOI: 10.1073/pnas.0600552103

Experimental method

X-RAY DIFFRACTION (1.401 Å)