[Light-dependent incorporation of selenite into selenocysteine by isolated chromatophore of Chromatium vinosum].
Illiminated intact chromatophore of chromatium vinosum in the presence of O-acetylserine(OAS) catalysed incorporation of SeO3(2-) into selenocysteine at rate of 359 nmol.mgBchl-1.h-1. Sonicated chromatophore catalysed SeO3(2-) incorporation at 1.1% of the rate of intact chromatophore. Addition of GSH and NADPH increased the rate to 88.3% of intact rate, but SeO3(2-) incorporation under these conditions was essentially light dependent. The purified GSH reductase from Chromatium vinosum in the presence of cysteine synthase OAs and NADPH catalysed incorporation of SeO3(2-) into selenocysteine. It is proposed that SeO3(2-) is reduced by light-coupled GSH reductase and that Se2- produced is incorporated into selenocysteine by cysteine synthase.
Wang
M
M
Department of Life Science of Shanxi University, Taiyuan 030006.
Jin
X
X
Guo
X
X
Qi
Y
Y
D002384:Catalysis; D002844:Chromatium / Q000187:drug effects / Q000378:metabolism*; D005978:Glutathione / Q000494:pharmacology; D005980:Glutathione Reductase / Q000494:pharmacology; D008027:Light; D009249:NADP / Q000494:pharmacology; D017279:Selenocysteine / Q000378:metabolism*; D012694:Serine / Q000031:analogs & derivatives* / Q000494:pharmacology; D018038:Sodium Selenite / Q000378:metabolism*
D017279:Selenocysteine; D012694:Serine; D009249:NADP; D005980:Glutathione Reductase; C043943:O-acetylserine; D005978:Glutathione; D018038:Sodium Selenite