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Kinetic characterization of the membrane-bound cytochromes of Escherichia coli grown under a variety of conditions by using a stopped-flow dual-wavelength spectrophotometer.

ABSTRACT: A study was made of the rapid oxidation kinetics of the cytochromes of Escherichia coli. The b-type cytochromes were kinetically heterogeneous, with one species (presumably cytochrome o) oxidized so rapidly that it could fully support observed oxidation rates. Cytochrome d but not cytochrome a1 was also kinetically competent to support respiration. However, in cells grown anaerobically in the presence of NO3-, cytochrome d exhibited slow oxidation kinetics and a red-shift in its reduced-minus-oxidized difference spectrum.

SUBMITTER: Haddock BA

PROVIDER: S-EPMC1172709 | biostudies-other | 1976 Feb

REPOSITORIES: biostudies-other

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