Isolation of a b-Type Cytochrome Oxidase from Membranes of the Phototrophic Bacterium Rhodopseudomonas capsulata
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چکیده
A cytochrome oxidase (EC 1.9.3.1) was solubilized from the membrane fraction of aerobically grown cells of Rhodopseudomonas capsulata by treatment with Triton X-100. The enzyme was purified 160 fold by chromatography on DEAE-Sepharose CL 6B and affinity chromatography on cytochrome c-thiol activated Sepharose 4B. The purified enzyme has a pH-optimum at 8.5 and a temperature optimum at 35 °C. The ap parent Km for reduced horse cytochrome c is 24 |iM (at pH 8 and 30 °C). The purified cytochrome oxidase was 50% inhibited by 1.5 |iM KCN and 10 (iM NaN,. The purified enzyme contained one polypeptide of mT 65,000 and 6-type cytochrome.
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تاریخ انتشار 2013