2oxh
From Proteopedia
The SOXYZ Complex of Paracoccus Pantotrophus
Overview
The bacterial Sox (sulfur oxidizing) system allows the utilization of inorganic sulfur compounds in energy metabolism. Central to this process is the SoxYZ complex that carries the pathway intermediates on a cysteine residue near the C terminus of SoxY. Crystal structures have been determined for Paracoccus pantotrophus SoxYZ with the carrier cysteine in the underivatized state, conjugated to the polysulfide mimic beta-mercaptoethanol, and as the sulfonate adduct pathway intermediate. The carrier cysteine is located on a peptide swinging arm and is bracketed on either side by diglycine dipeptides acting as molecular universal joints. This structure provides a novel solution to the requirement that the cysteine-bound intermediates be able to access and orient themselves within the active sites of multiple partner enzymes. Adjacent to the swinging arm there is a conserved, deep, apolar pocket into which the beta-mercaptoethanol adduct extends. This pocket would be well suited to a role in protecting labile pathway intermediates from adventitious reactions.
About this Structure
2OXH is a Protein complex structure of sequences from Paracoccus denitrificans. Full crystallographic information is available from OCA.
Reference
The SoxYZ complex carries sulfur cycle intermediates on a peptide swinging arm., Sauve V, Bruno S, Berks BC, Hemmings AM, J Biol Chem. 2007 Aug 10;282(32):23194-204. Epub 2007 May 23. PMID:17522046 Page seeded by OCA on Sun May 4 11:52:27 2008
