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Stereochemistry of phytoene biosynthesis by isolated chloroplasts.

ABSTRACT: The incorporation of [2-(14)C,(5R)-5-(3)H(1)]MVA* and [2-(14)C,5-(3)H(2)]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 of mevalonate. All the pro-R hydrogen atoms from C-5 of mevalonate are retained. These results with a cell-free system confirm and extend the observations made in previous work with tomato slices.

SUBMITTER: Buggy MJ

PROVIDER: S-EPMC1184938 | biostudies-other | 1969 Sep

REPOSITORIES: biostudies-other

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Incorporation of 2-[14C]mevalonic acid into phytoene by isolated chloroplasts.

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