title: Membrane D-lactate oxidase in Zymomonas mobilis: evidence for a branched respiratory chain.
abstract: Respiratory chain composition of the ethanol-producing bacterium Zymomonas mobilis was studied. Its membrane D-lactate oxidase was characterised. With NADH, but not D-lactate as substrate, a cytochrome o-like component was seen in CO difference spectra. Chlorpromazine specifically inhibited reduction of cytochrome d, while myxothiazol eliminated the cytochrome o-like features in CO difference spectra. It is suggested that electrons from NADH are distributed between branches terminated by the cytochrome o-like component, cytochrome a, and cytochrome d. With D-lactate, electrons are transported to cytochrome a, or an unidentified CN(-)-sensitive oxidase, and cytochrome d.
authors.affiliation: Institute of Microbiology and Biotechnology, University of Latvia, Riga, Latvia.
authors.forename: U
authors.initials: U
authors.lastname: Kalnenieks
authors.forename: N
authors.initials: N
authors.lastname: Galinina
authors.forename: S
authors.initials: S
authors.lastname: Bringer-Meyer
authors.forename: R K
authors.initials: RK
authors.lastname: Poole
mesh_terms: D000332:Aerobiosis; D002746:Chlorpromazine / Q000494:pharmacology; D003580:Cytochromes / Q000378:metabolism; D004579:Electron Transport; D019344:Lactic Acid / Q000378:metabolism*; D008689:Methacrylates; D006899:Mixed Function Oxygenases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009097:Multienzyme Complexes / Q000378:metabolism; D009243:NAD / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D010101:Oxygen Consumption; D013053:Spectrophotometry; D013844:Thiazoles / Q000494:pharmacology; D017355:Zymomonas / Q000201:enzymology* / Q000254:growth & development
chemical_list: D003580:Cytochromes; D008689:Methacrylates; D009097:Multienzyme Complexes; D013844:Thiazoles; D009243:NAD; D019344:Lactic Acid; C030517:myxothiazol; D006899:Mixed Function Oxygenases; C021497:lactate 2-monooxygenase; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases; D002746:Chlorpromazine