Component A of the methyl coenzyme M methylreductase system of Methanobacterium: resolution into four components.
نویسندگان
چکیده
Component A, the oxygen-sensitive protein fraction of the methyl coenzyme M methylreductase system of Methanobacterium thermoautotrophicum, has been stabilized and resolved into three protein fractions and one cofactor that are required to reconstitute component A activity. Component A1 is oxygen-stable and contains hydrogen-dependent deazaflavin (coenzyme F420)-reducing activity. Component A2 is acidic; components A2 and A3 are oxygen sensitive. The specific functions of each component in methyl group reduction are unknown. Resolution of component A revealed a new cofactor requirement of the methylreductase system for FAD. Hydrogen-dependent reduction of methyl coenzyme M to methane and coenzyme M, the terminal step of CO2 reduction by methanogenic bacteria, requires protein components A1, A2, A3, and C in addition to component B, FAD, ATP, and Mg2+.
منابع مشابه
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ورودعنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 80 8 شماره
صفحات -
تاریخ انتشار 1983