1h32
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REDUCED SOXAX COMPLEX FROM RHODOVULUM SULFIDOPHILUM
OverviewOverview
Reduced inorganic sulfur compounds are utilized by many bacteria as, electron donors to photosynthetic or respiratory electron transport, chains. This metabolism is a key component of the biogeochemical sulfur, cycle. The SoxAX protein is a heterodimeric c-type cytochrome involved in, thiosulfate oxidation. The crystal structures of SoxAX from the, photosynthetic bacterium Rhodovulum sulfidophilum have been solved at 1.75, A resolution in the oxidized state and at 1.5 A resolution in the, dithionite-reduced state, providing the first structural insights into the, enzymatic oxidation of thiosulfate. The SoxAX active site contains a haem, with unprecedented cysteine persulfide (cysteine sulfane) coordination., This unusual post-translational modification is also seen in, sulfurtransferases such as rhodanese. Intriguingly, this enzyme shares, further active site characteristics with SoxAX such as an adjacent, conserved arginine residue and a strongly positive electrostatic, potential. These similarities have allowed us to suggest a catalytic, mechanism for enzymatic thiosulfate oxidation. The atomic coordinates and, experimental structure factors have been deposited in the PDB with the, accession codes 1H31, 1H32 and 1H33.
About this StructureAbout this Structure
1H32 is a Protein complex structure of sequences from Rhodovulum sulfidophilum with and as ligands. Known structural/functional Site: . Full crystallographic information is available from OCA.
ReferenceReference
Structural basis for the oxidation of thiosulfate by a sulfur cycle enzyme., Bamford VA, Bruno S, Rasmussen T, Appia-Ayme C, Cheesman MR, Berks BC, Hemmings AM, EMBO J. 2002 Nov 1;21(21):5599-610. PMID:12411478
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