title: Diglycosyl diacylglycerol of Mycobacterium tuberculosis.
abstract: A diglycosyl diacylglycerol was isolated from Mycobacterium tuberculosis, and its structure was established by a combination of methylation analysis, 1H nuclear magnetic resonance, and fast atom bombardment-mass spectrometry. It is a 1,2-diacyl-[beta-D-glucopyranosyl(1"----6')-beta-D-glucopyranosyl(1'---- 3)]- sn-glycerol and exists in at least five molecular species differing in fatty acyl substituents. The major constituent fatty acids were identified as iso- and anteisopentadecanoate, iso- and n-hexadecanoate, and iso- and anteisoheptadecanoate. Although glycosyl diacylglycerols are common membrane components of gram-positive bacteria, this report represents the first substantial evidence for the presence of a glycosyl diacylglycerol within a member of the Mycobacterium genus. Although the glycolipid is not a major component of M. tuberculosis, it reacts readily in enzyme-linked immunosorbent assay against rabbit antibodies raised against whole bacteria and thus may be useful for the serodiagnosis of tuberculosis.
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology; D055598:Chemical Phenomena; D002621:Chemistry; D004075:Diglycerides / Q000032:analysis / Q000276:immunology / Q000302:isolation & purification*; D005227:Fatty Acids / Q000032:analysis; D005989:Glycerides / Q000302:isolation & purification*; D006017:Glycolipids / Q000032:analysis / Q000276:immunology / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009169:Mycobacterium tuberculosis / Q000032:analysis* / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D004075:Diglycerides; D005227:Fatty Acids; D005989:Glycerides; D006017:Glycolipids