title: 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'.
mesh_terms: D002250:Carbon Radioisotopes; D002338:Carotenoids / Q000096:biosynthesis*; D005417:Flavobacterium / Q000378:metabolism*; D005898:Glass; D008798:Mevalonic Acid / Q000378:metabolism; D010084:Oxidation-Reduction; D014316:Tritium
chemical_list: D002250:Carbon Radioisotopes; D014316:Tritium; D002338:Carotenoids; D008798:Mevalonic Acid