مرکز منطقه ای اطلاع رساني علوم و فناوري - The polar-lipid composition of the sphingolipid-producing bacterium Flectobacillus major

Latin Abstract :

Polar lipids comprise about 90% of the total chloroform-methanol extractable lipids of the Gram-negative, fresh-water, ring-forming bacterium Flectobacillus major FM and consist of at least 10 constituents. These are aminophosphosphingolipids, 2-N-(2′- -hydroxy-13′-methyltetradecanoyl)-15-methyl-4(E)-hexadecasphingenyl-1-phosphoethanolamine (36.8% of the total polar lipids) and its 2′-deoxy derivative (3.7%); sulfonic-acid analogues of ceramide, 2- -(2′- -hydroxy-13′-methyltetradecanoyl)amino-3- -hydroxy-15-methylhexadecane-1-sulfonic acid (18.1%) and its 2′-deoxy derivative (3.5%); a lipoamino acid, N-[3- -(15′-methylhexadecanoyloxy)-15-methylhexadecanoyl]-glycine (3.7%); a lipodipeptide, N-{N′-[3″- -(15 -methylhexadecanoyloxy)-15″-methylhexadecanoyl]glycyl}- -serine (7.8%); 1,2-diacyl-sn-glycero-3-phosphoethanolamine (7.7%), 1,2-diacyl-3-α- -galactopyranosyl-sn-glycerol (2.9%); ceramide phospho-myo-inositol (4.9%), and a previously described unusual glycosphingolipid, 7-deoxy-7-amino- -manno-heptulosonopyranosyl (1-hydroxycarbonyl-6-deoxy-6-amino-α- -mannopyranosyl) ceramide (10.9%); the last two lipids contain only 15-methyl-4(E)-hexadecasphingenine as a long-chain base. The sole structural type of amide-bound fatty acids in the sphingolipids, including the sulfonic-acid analogues, is iso-15:0, either non-hydroxylated or hydroxylated at 2-C, whereas 15-methylhexadecanoic acid is the major ester-bound fatty acid in the remaining lipids.