title: Rapid analysis of Listeria monocytogenes cell wall teichoic acid carbohydrates by ESI-MS/MS.
abstract: We report the application of electrospray ionization (ESI) mass spectrometry for compositional characterization of wall teichoic acids (WTA), a major component of gram-positive bacterial cell walls. Tandem mass spectrometry (ESI-MS/MS) of purified and chemically hydrolyzed monomeric WTA components provided sufficient information to identify WTA monomers and their specific carbohydrate constituents. A lithium matrix was used for ionization of uncharged WTA monomers, and successfully applied to analyze the WTA molecules of four Listeria strains differing in carbohydrate substitution on a conserved polyribitol-phosphate backbone structure. Carbohydrate residues such as N-acetylglucosamine or rhamnose linked to the WTA could directly be identified by ESI-MS/MS, circumventing the need for quantitative analysis by gas chromatography. The presence of a terminal N-acetylglucosamine residue tethered to the ribitol was confirmed using fluorescently labeled wheat-germ agglutinin. In conclusion, the mass spectrometry method described here will greatly facilitate compositional analysis and characterization of teichoic acids and similar macromolecules from diverse bacterial species, and represents a significant advance in the identification of serovar-specific carbohydrates and sugar molecules on bacteria.
authors: Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.
authors: Marcel R
authors: MR
authors: Eugster
authors: Martin J
authors: MJ
authors: Loessner
mesh_terms: D002241:Carbohydrates / Q000032:analysis* / Q000737:chemistry; D002473:Cell Wall / Q000737:chemistry*; D008089:Listeria monocytogenes / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013682:Teichoic Acids / Q000737:chemistry*
chemical_list: D002241:Carbohydrates; D013682:Teichoic Acids