Isoelectric Focusing of the NAD(P)H-Cytochrome c Reductase Subunit of Chlamydomonas reinhardii Nitrate Reductase
نویسنده
چکیده
Isoelectric Focusing, Nitrate Reductase, Diaphorase, Chlamydomonas reinhardii Chlamydomonas reinhardii 104 mutant strain cells contain many NAD(P)H-cytochrom e c reductase activities unrelated to nitrate reduction in addition to an NAD(P)H-cytochrom e c reductase related to NAD(P)H-nitrate reductase, which have molecular weights from 37000 to 124000. By combining chromatographic procedures and preparative isoelectric focusing, three major fractions o f NAD(P)H-cytochrom e c reductase were isolated with pi at 7.1, 5.5 and 5.05, respectively. O f these fractions, only the last one was identified as the diaphorase subunit o f the NAD(P)H-nitrate reductase by its ability to reconstitute in vitro the nitrate reductase native complex upon complementation with active terminal nitrate reductase o f 305 mutant o f C. reinhardii.
منابع مشابه
Nitrate Reductase from a Mutant Strain of Chlamydomonas reinhardii Incapable of Nitrate Assimilation
Nitrate reductase from mutant 305 o f Chlamydomonas reinhardii has been purified about 90-fold and biochemically characterized. The enzyme can use reduced flavins and viologens as electron donors to reduce nitrate but, unlike the nitrate reductase com plex from its parental wild strain, lacks NAD(P)H-nitrate reductase and NAD(P)H-cytochrom e c reductase activities, does not bind to Blue-Agarose...
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