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Carotenoid biosynthesis in a Flavobacterium sp.: stereochemistry of hydrogen elimination in the desaturation of phytoene to lycopene, rubixanthin and zeaxanthin.

ABSTRACT: [2-(14)C,(2R)-2-(3)H(1)]- and [2-(14)C,(2S)-2-(3)H(1)]-Mevalonates were rapidly incorporated into phytoene, lycopene, rubixanthin and zeaxanthin in a Flavobacterium system obtained by disruption of the bacterial cells by shaking with glass beads. Four hydrogen atoms arising from the 2-pro-S-hydrogen atoms of mevalonate were lost in the desaturation of phytoene to lycopene, rubixanthin and zeaxanthin. The desaturation of phytoene involves trans-elimination of hydrogen in the introduction of the double bonds at C-7, C-11, C-7' and C-11'.

SUBMITTER: McDermott JC

PROVIDER: S-EPMC1177920 | biostudies-other | 1973 Aug

REPOSITORIES: biostudies-other

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