Chemical structure of lipid A isolated from Flavobacterium meningosepticum lipopolysaccharide.
The chemical structure of the lipid A of the lipopolysaccharide component isolated from Flavobacterium meningosepticum IFO 12535 was elucidated. Methylation and nuclear magnetic resonance analyses showed that two kinds of hydrophilic backbone exist in the free lipid A: a beta (1-->6)-linked 2-amino-2-deoxy-D-glucose, which is usually present in enterobacterial lipid A's, and a 2-amino-6-O-(2, 3-diamino-2,3-dideoxy-beta-D-glucopyranosyl)-2-deoxy-D-glucose, in a molar ratio of 1.00:0.35. Both backbones were alpha-glycosidically phosphorylated in position 1, and the hydroxyl groups at positions 4, 4', and 6' were unsubstituted. Liquid secondary ion-mass spectrometry revealed a pseudomolecular ion at m/z 1673 [M-H]- as a major monophosphoryl lipid A component carrying five acyl groups. Fatty acid analysis showed that the lipid A contained 1 mol each of amide-linked (R)-3-OH iC17:0, ester-linked (R)-3-OH iC15:0, amide-linked (R)-3-O-(iC15:0)-iC17:0, and both amide- and ester-linked (R)-3-OH C16:0. Fatty acid distribution analyses using several mass spectrometry determinations demonstrated that the former two constituents were distributed on positions 2 and 3 of the reducing terminal unit of the backbones and that the latter two were attached to the 2' and 3' positions in the nonreducing terminal residue.
Kato
H
H
Division of Microbiology, National Institute of Health Sciences, Setagayaku, Tokyo 158, Japan.
Haishima
Y
Y
Iida
T
T
Tanaka
A
A
Tanamoto
K
K
D000577:Amides; D002849:Chromatography, Gas; D004187:Disaccharides / Q000737:chemistry; D004952:Esters; D005417:Flavobacterium / Q000737:chemistry* / Q000276:immunology; D008401:Gas Chromatography-Mass Spectrometry; D008050:Lipid A / Q000737:chemistry* / Q000302:isolation & purification; D008070:Lipopolysaccharides / Q000737:chemistry; D008745:Methylation; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular
D000577:Amides; D004187:Disaccharides; D004952:Esters; D008050:Lipid A; D008070:Lipopolysaccharides