Novel methylated triterpenoids of the gammacerane series from the nitrogen-fixing bacterium Bradyrhizobium japonicum USDA 110.
The nitrogen-fixing, symbiotic root-nodule forming bacterium Bradyrhizobium japonicum USDA 110 contained gammacerane derivatives next to triterpenoids of the hopane series. Diploptene, diplopterol, 2 beta-methyldiplopterol, aminobacteriohopanetriol and adenosylhopane were accompanied by tetrahymanol and the corresponding novel methylated homologues 2 beta-methyltetrahymanol, 20 alpha-methyltetrahymanol, and 2 beta,20 alpha-dimethyltetrahymanol. Incorporation of [(2)H(3)]methyl-L-methionine indicated that the additional methyl groups originated from methionine, probably with S-adenosylmethionine acting as methyl donor, with retention of the three deuterium atoms. The simultaneous presence of hopane and gammacerane derivatives seems a characteristic feature of the genus Bradyrhizobium and the phylogenetically closely related Rhodopseudomonas palustris.
Université Louis Pasteur/CNRS, Institut Le Bel, Strasbourg, France.
J M
JM
Bravo
M
M
Perzl
T
T
Härtner
E L
EL
Kannenberg
M
M
Rohmer
D020369:Bradyrhizobium / Q000737:chemistry* / Q000378:metabolism; D002855:Chromatography, Thin Layer; D003500:Cyclization; D003903:Deuterium / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D008190:Lyases / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008715:Methionine / Q000031:analogs & derivatives / Q000378:metabolism; D008745:Methylation; D010802:Phylogeny; D011106:Polyisoprenyl Phosphates / Q000378:metabolism; D012241:Rhodopseudomonas / Q000737:chemistry / Q000378:metabolism; D012436:S-Adenosylmethionine / Q000378:metabolism; D013559:Symbiosis; D014315:Triterpenes / Q000737:chemistry / Q000378:metabolism*
D011106:Polyisoprenyl Phosphates; D014315:Triterpenes; D012436:S-Adenosylmethionine; D008715:Methionine; D003903:Deuterium; C038344:methionine methyl ester; D008190:Lyases; C022651:squalene cyclase