Isolation and characterization of a novel glucuronosyl diacylglycerol from Mycobacterium smegmatis.
A glucuronic acid-containing diacylglycerol was isolated from exponentially growing Mycobacterium smegmatis. Structural analysis of the purified glycolipid, performed by gas chromatography-mass spectrometry, fast atom bombardment-mass spectrometry, and high resolution proton NMR, indicated the structure 3-(O-alpha-D-glucuronopyranosyl)-1,2-diacyl-sn-glycerol. Two forms of the glycolipid were observed differing in fatty acid composition. Both molecular species contained a hexadecanoic acid residue, whereas the second acyl group was either tuberculostearic acid (10-methylstearic acid) or octadecenoic acid. The inherent antigenicity of the glycolipid was shown by its ability to bind to anti-Mycobacterium avium (serovar 26) and anti-Mycobacterium tuberculosis sera by Western blot-type thin-layer chromatography. This is the second instance of the isolation of a glycosyl diacylglycerol from members of the Mycobacterium genus, further confirming its close relationship to Gram-positive bacteria.
Microbiology and Genetics Unit, University of Louvain, Medical School, Brussels, Belgium.
B A
BA
Wolucka
M R
MR
McNeil
L
L
Kalbe
C
C
Cocito
P J
PJ
Brennan
D000942:Antigens, Bacterial / Q000302:isolation & purification*; D002240:Carbohydrate Sequence; D005227:Fatty Acids / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D006017:Glycolipids / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009161:Mycobacterium / Q000737:chemistry*; D010169:Palmitic Acids / Q000032:analysis; D016339:Spectrometry, Mass, Fast Atom Bombardment
D000942:Antigens, Bacterial; D005227:Fatty Acids; D006017:Glycolipids; D010169:Palmitic Acids; C014573:glucuronosyl diacylglycerol