Novel lipids of Butyrivibrio spp

(1) An analysis has been conducted of the lipids present in three obligately anaerobic bacteria isolated from the ovine rumen belonging to the genus Butyrivibrio. Two of these organisms are rich in phospholipase (A1 + A2) activity, and appear to be different strains of the species fibrisolvens. (2) The only N-containing lipids comprise N-acyl-phosphatidylethanolamine occurring as a minor component in all organisms and a new lipid, diglyceride galactosylphosphorylethanolamine in one of these. (3) All three organisms contained the n-butyryl ester of phosphatidyl-glycerol and in one this represented the major phospholipid present. Valeryl, iso-valeryl, propionyl and myristoyl esters of phosphatidylglycerol were also detected. (4) Two organisms contained glycerylphosphorylgalactosyldiglyceride and one of these also contained a large proportion of a less polar galactophospholipid which is probably a diacyl derivative of the former lipid. (5) All three organisms contained monogalactofuranosyl diglyceride and from one a n-butyryl ester of this galactolipid was isolated. (6) In all of the lipids examined the "diglyceride' moiety consisted almost entirely of plasmalogenic diglyceride (alk-1-enyl, acyl, glycerol).