Mycobacterial envelope lipids fingerprint from direct MALDI-TOF MS analysis of intact bacilli. Issue 1 (January 2015)

• Record Type: Journal Article
• Authors: Larrouy-Maumus, Gérald; Puzo, Germain
• Is Part Of: Tuberculosis. Volume 95:Issue 1(2015)
• Page Start: 75
• Page End: 85
• Publication Date: 2015-01
• Subjects: Lipids -- Mass spectrometry -- Phenotypic characterization; DE diethyl ether -- DHB 2, 5-dihydroxybenzoic acid -- GPL glycopeptidolipids -- GroMM glycerol monomycolate -- HPA hydroxyphthioceranoic acid -- LOSs lipooligosaccharides -- MALDI-TOF MS Matrix-assisted laser desorption/ionization-time of flight-mass spectrometry -- MeOH methanol -- M. tuberculosis Mycobacterium tuberculosis -- NTM non-tuberculous mycobacteria -- TAG triacylglycerol -- TB tuberculosis -- TDM trehalose dimycolate -- PBMCs peripherical blood mononuclear cell -- PAT pentaacyltrehalose -- PE petroleum ether -- PGL phenol glycolipid -- PIM phosphatidyl-myo-inositol mannosides -- SGL sulfoglycolipid -- In AcxSGL x refers to the total number of acyl groups whatever the nature of the fatty acids -- In AcxPIMy x refers to the number of acyl groups esterified to available hydroxyls on the Manp or myo-inositol residues, y refers to the number of Manp residues; 616.995
• DOI: 10.1016/j.tube.2014.11.001
• Languages: English
• ISSNs: 1472-9792

Abstract

Summary: Mycobacterium tuberculosis (Mtb) lipids including glycolipids and lipoglycans play a crucial role in the modulation of the host immune response by targeting the innate receptors C-type lectins, TLRs and the CD1 proteins of class 1. Glycolipids have been shown to be biomarkers of M. tuberculosis strains and also of opportunistic mycobacteria called non-tuberculous mycobacteria. Most of the structural and functional work of the Mtb lipids has been done using lipids arising from M. tuberculosis cell growth in vitro . However it is likely that lipid structures can change during infection or among the M. tuberculosis or opportunistic clinical strains. Here we describe a new, rapid and sensitive analysis of lipids directly on whole mycobacteria which can be done in few minutes and on less than 1000 mycobacteria by direct matrix-assisted laser desorption/ionization mass spectrometry using an unusual solvent matrix. By this new methodology, which does not require extraction or purification steps, we are able to discriminate mycobacteria belonging to the Mtb complex as well as opportunistic and non-pathogenic mycobacteria. This method was also found to be successful for identification of an envelope lipid mutant. This work opens a new analytical route for in vivo analysis of mycobacterial lipids.