title: Carotenoids of rhizobia. II. The effect of nicotine on the carotenoid pattern of Rhizobium lupini.
abstract: With increasing concentrations in the growth medium of the cyclization inhibitors nicotine or 2-(4-chlorophenylthio)-triethylamine hydrochloride (CPTA) the previously identified bicyclic carotenoids of Rhizobium lupini (2,3,2',3'-tetrahydroxy-beta,beta-caroten-4-one and 2,3,2',3'-tetrahydroxy-beta,beta-carotene) were successively replaced by hitherto unknown monocyclic carotenoids. By application of mass and nuclear magnetic resonance spectroscopy 3 carotenoids were identified as 2,3-trans-dihydroxy-beta,psi-caroten-4-one, 2,3-trans-dihydroxy-beta,psi-carotene, and 3-hydroxy-beta,psi-caroten-4-one. A further compound was tentatively established as (2- or 3-)monohydroxy-beta,psi-carotene. It was found that other inhibitors such as diphenylamine or 4-chloro-5-(dimethylamino)-2-alpha,alpha,alpha(trifluoro-m-tolyl)-3-(2H)-pyridazinone (San 6706) did not affect the pigment pattern. The results are discussed in relation to carotenoid biosynthesis in Rhizobium lupini.
mesh_terms: D002338:Carotenoids / Q000096:biosynthesis*; D055598:Chemical Phenomena; D002621:Chemistry; D004159:Diphenylamine / Q000494:pharmacology; D005021:Ethylamines; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009538:Nicotine / Q000494:pharmacology*; D010627:Phenethylamines / Q000494:pharmacology; D012231:Rhizobium / Q000378:metabolism*; D013440:Sulfides / Q000494:pharmacology
chemical_list: D005021:Ethylamines; D010627:Phenethylamines; D013440:Sulfides; C007143:2-(4-chlorophenylthio)triethylamine; D002338:Carotenoids; D009538:Nicotine; D004159:Diphenylamine