The Hydrogenase System of Clostridium pasteurianum
نویسندگان
چکیده
Peck and Gest (1) reported that crude extracts of Clostridium butylicum produce small amounts of hydrogen from aqueous dithionite (hydrosulfite). Hydrogen evolution from dithionite decreased upon dilution of the crude extracts and was lost upon further purification (2). This loss of activity was interpreted on the basis of a cofactor requirement or loss of an essential enzyme. Evolution of hydrogen was greatly enhanced by the addition of the electron-accepting dyes, methyl or benzyl viologen. The reduced dyes are readily oxidized by hydrogenase; this finding was the basis of an assay for hydrogenase described by Peck and Gest (1, 2). We have observed similar findings with Clostridium pasteuriunum and have found that crude extracts catalyze the evolution of hydrogen gas from dithionite. The hydrogenevolving system has been separated into two components; one of these contains hydrogenase and the other an electron-transferring protein which couples with hydrogenase in the formation of hydrogen gas from dithionite. This factor contains iron and has been named “ferredoxin.” Ferredoxin is believed to function as follows:
منابع مشابه
Efficiency of ferredoxins and flavodoxins as mediators in systems for hydrogen evolution.
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