1jnr
Structure of adenylylsulfate reductase from the hyperthermophilic Archaeoglobus fulgidus at 1.6 resolution
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OverviewOverview
The iron-sulfur flavoenzyme adenylylsulfate (adenosine 5'-phosphosulfate, APS) reductase catalyzes reversibly the reduction of APS to sulfite and, AMP. The structures of APS reductase from the hyperthermophilic, Archaeoglobus fulgidus in the two-electron reduced state and with sulfite, bound to FAD are reported at 1.6- and 2.5- resolution, respectively. The, FAD-sulfite adduct was detected after soaking the crystals with APS. This, finding and the architecture of the active site strongly suggest that, catalysis involves a nucleophilic attack of the N5 atom of reduced FAD on, the sulfur atom of APS. In view of the high degree of similarity between, APS reductase and fumarate reductase especially with regard to the, FAD-binding alpha-subunit, it is proposed that both subunits originate, from a common ancestor resembling archaeal APS reductase. The two, electrons required for APS reduction are transferred via two [4Fe-4S], clusters from the surface of the protein to FAD. The exceptionally large, difference in reduction potential of these clusters (-60 and -500 mV) can, be explained by interactions of the clusters with the protein matrix.
About this StructureAbout this Structure
1JNR is a Protein complex structure of sequences from Archaeoglobus fulgidus with FAD, SF4 and GOL as ligands. Active as Adenylyl-sulfate reductase, with EC number 1.8.99.2 Full crystallographic information is available from OCA.
ReferenceReference
Structure of adenylylsulfate reductase from the hyperthermophilic Archaeoglobus fulgidus at 1.6-A resolution., Fritz G, Roth A, Schiffer A, Buchert T, Bourenkov G, Bartunik HD, Huber H, Stetter KO, Kroneck PM, Ermler U, Proc Natl Acad Sci U S A. 2002 Feb 19;99(4):1836-41. Epub 2002 Feb 12. PMID:11842205
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