Membrane-associated chromate reductase activity from Enterobacter cloacae.
نویسندگان
چکیده
Washed cells of Enterobacter cloacae HO1 reduced hexavalent chromium (chromate: CrO4(2-) anaerobically. Chromate reductase activity was preferentially associated with the membrane fraction of the cells. Right-side-out membrane vesicles prepared from E. cloacae cells showed high chromate reductase activities when ascorbate-reduced phenazine methosulfate was added as an electron donor.
منابع مشابه
Selenate reduction by Enterobacter cloacae SLD1a-1 is catalysed by a molybdenum-dependent membrane-bound enzyme that is distinct from the membrane-bound nitrate reductase.
Enterobacter cloacae SLD1a-1 is capable of reducing selenium oxyanions to elemental selenium under both aerobic and anaerobic conditions. In this study the enzyme that catalyses the initial reduction of selenate (SeO4(2-)) to selenite (SeO3(2-)) has been localised to isolated cytoplasmic membrane fractions. Experiments with intact cells have shown that the putative selenate reductase can accept...
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متن کاملReduction of Selenium Oxyanions by Enterobacter cloacae SLD1a-1: Isolation and Growth of the Bacterium and Its Expulsion of Selenium Particles.
A facultative bacterium capable of removing the selenium (Se) oxyanions selenate (SeO(inf4)(sup2-)) and selenite (SeO(inf3)(sup2-)) from solution culture in flasks open to the atmosphere was isolated and studied with the goal of assessing its potential for use in bioremediation of seleniferous agricultural drainage water. Elemental Se (Se(sup0)) was confirmed as a product of the reaction. The o...
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 172 3 شماره
صفحات -
تاریخ انتشار 1990