Membrane D-lactate oxidase in Zymomonas mobilis: evidence for a branched respiratory chain
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Published on: October 30, 2015
U Kalnenieks1, N Galinina, S Bringer-Meyer
1Institute of Microbiology and Biotechnology, University of Latvia, Riga, Latvia.
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.
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