1e83
From Proteopedia
Cytochrome c' from Alcaligenes xylosoxidans - oxidized structure
Structural highlights
FunctionCYCP_ALCXX Cytochrome c' is the most widely occurring bacterial c-type cytochrome. Cytochromes c' are high-spin proteins and the heme has no sixth ligand. Their exact function is not known. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedMicrobial cytochromes c' contain a 5-coordinate His-ligated heme that forms stable adducts with nitric oxide (NO) and carbon monoxide (CO), but not with dioxygen. We report the 1.95 and 1.35 A resolution crystal structures of the CO- and NO-bound forms of the reduced protein from Alcaligenes xylosoxidans. NO disrupts the His-Fe bond and binds in a novel mode to the proximal face of the heme, giving a 5-coordinate species. In contrast, CO binds 6-coordinate on the distal side. A second CO molecule, not bound to the heme, is located in the proximal pocket. Since the unusual spectroscopic properties of cytochromes c' are shared by soluble guanylate cyclase (sGC), our findings have potential implications for the activation of sGC induced by the binding of NO or CO to the heme domain. Unprecedented proximal binding of nitric oxide to heme: implications for guanylate cyclase.,Lawson DM, Stevenson CE, Andrew CR, Eady RR EMBO J. 2000 Nov 1;19(21):5661-71. PMID:11060017[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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