Great Bntain 641 Stereochemistry of Phytoene Biosynthesis by Isolated Chloroplasts
نویسنده
چکیده
The incorporation of 12-14C,(5R)-5-3Hj]MVA* and 12-14C,5-3H2]MVA into geranylgeraniol and phytoene by a preparation of 'non-aqueous' bean leaf chloroplasts has been studied. In the formation of phytoene from two molecules of geranylgeranyl pyrophosphate, the loss of hydrogen is stereospecific, the hydrogen atom lost from C-1 of each molecule of geranylgeranyl pyrophosphate being that which was originally the pro-S hydrogen atom from C-5 ofmevalonate. All the pro-
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