Carotenoids and related compounds. Part XXIII. Occurrence of 7,8,11,12-tetrahydrolycopene, spheroidene, 3,4,11′,12′-tetrahydrospheroidene, and 11′,12′-dihydrospheroidene in Rhodospirillum rubrum

摘要: Four carotenoids isolated from diphenylamine-inhibited cultures of Rhodospirillum rubrum have been identified by light absorption spectroscopy and mass spectrometry as 7,8,11,12-tetrahydrolycopene (IV), spheroidene (IX), 3,4,11′,12′-tetrahydrospheroidene (VII), 11′,12′-dihydrospheroidene (XII).The recognition (IV) suggests the need for a modification Porter-Lincoln series in these photosynthetic bacteria, presence other three pigments indicates that alternative pathways spirilloxanthin biosynthesis may be operating.