title: Characterization of sulfolipids of Mycobacterium tuberculosis H37Rv by multiple-stage linear ion-trap high-resolution mass spectrometry with electrospray ionization reveals that the family of sulfolipid II predominates.
abstract: Mycobacterium tuberculosis, the causative agent of tuberculosis, is unique among bacterial pathogens in that it contains a wide array of complex lipids and lipoglycans on its cell wall. Among them, the sulfated glycolipid, termed the sulfolipid, is thought to mediate specific host-pathogen interactions during infection. Sulfolipids (SLs), including sulfolipid I (SL-I) and sulfolipid II (SL-II), are 2,3,6,6'-tetraacyltrehalose 2'-sulfates. SL-I was identified as a family of homologous 2-palmitoyl(stearoyl)-3-phthioceranoyl-6,6'-bis(hydroxyphthioceranoy1)trehalose 2'-sulfates and was believed to be the principal sulfolipid of M. tuberculosis strain H37Rv. We cultured and extracted sulfolipids using various conditions, including those originally described, and employed high-resolution multiple-stage linear ion-trap mass spectrometry with electrospray ionization to characterize the structure of the principal SL. We revealed that SL-II, a family of homologous 2-stearoyl(palmitoyl)-3,6,6'-tris(hydroxyphthioceranoy1)trehalose 2'-sulfates, rather than SL-I is the principal sulfolipid class. We identified a great number of isomers resulting from permutation of the various hydroxyphthioceranoyl substituents at positions 6 and 6' of the trehalose backbone for each of the SL-II species in the entire family. We redefined the structure of this important lipid family that was misassigned using the traditional methods 40 years ago.
authors.affiliation: Department of Microbiology and Immunology, C5 109 Vet Medical Center, Cornell University, Ithaca, New York 14853, United States.
authors.forename: Elizabeth R
authors.initials: ER
authors.lastname: Rhoades
authors.forename: Cassandra
authors.initials: C
authors.lastname: Streeter
authors.forename: John
authors.initials: J
authors.lastname: Turk
authors.forename: Fong-Fu
authors.initials: FF
authors.lastname: Hsu
mesh_terms: D002240:Carbohydrate Sequence; D003470:Culture Media; D008055:Lipids / Q000737:chemistry* / Q000145:classification* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D009169:Mycobacterium tuberculosis / Q000737:chemistry* / Q000254:growth & development / Q000472:pathogenicity; D021241:Spectrometry, Mass, Electrospray Ionization; D013237:Stereoisomerism; D053719:Tandem Mass Spectrometry
chemical_list: D003470:Culture Media; D008055:Lipids; C015518:sulfolipids