title: The terminal respiratory chain of the methylotrophic bacterium Methylophilus methylotrophus.
abstract: Cytochrome oxidase o has been isolated from the obligately aerobic, methylotrophic bacterium Methylophilus methylotrophus in the form of a cytochrome cL-o complex. The latter is comprised of cytochrome cL (Mr 21 000) and cytochrome o (Mr 29 000) in a 1-2:1 ratio, possibly in association with one or more minor polypeptides; the complex exhibits a high ascorbate-TMPD oxidase activity which is inhibited non-competitively by cyanide (Ki approximately 2 microM). In contrast, the oxidation of methanol by whole cells is inhibited uncompetitively by cyanide (Ki approximately 4 microM), thus indicating the involvement in methanol oxidation of cytochrome oxidase aa3 rather than o.
mesh_terms: D001419:Bacteria / Q000201:enzymology / Q000378:metabolism*; D003486:Cyanides / Q000494:pharmacology*; D004579:Electron Transport / Q000187:drug effects; D003576:Electron Transport Complex IV / Q000037:antagonists & inhibitors / Q000302:isolation & purification*; D000432:Methanol / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects
chemical_list: D003486:Cyanides; D003576:Electron Transport Complex IV; D000432:Methanol