title: Analysis of bacterial strains with pyrolysis-gas chromatography/differential mobility spectrometry.
abstract: Eight vegetative bacterial strains and two spores were characterized by pyrolysis-gas chromatography with differential mobility spectrometry (py-GC/DMS) yielding topographic plots of ion intensity, retention time, and compensation voltage simultaneously for ions in positive and negative polarity. Biomarkers were found in the pyrolysate at characteristic retention times and compensation voltages and were confirmed by standard addition with GC/MS analyses providing discrimination between Gram negative and Gram positive bacterial types, but no recognition of individual strains within the Gram negative bacteria. Principal component analysis was applied using two dimensional data sets of ion intensity versus retention time at five compensation voltages including the reactant ion peaks all in positive and negative ion polarity. Clustering was observed with compensation voltage (CV) chromatograms associated with ion separation in the DMS detector and little or no clustering was observed with the reactant ion peaks or CV chromatograms where ion separation is poor. Consistent clustering of Gram positive B. odysseyi and Gram negative E. coli in both positive and negative polarities with the reactant ion peak chromatograms and key CV chromatograms suggests common but unknown common chemical compositions in the pyrolysate.
authors.affiliation: Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico 88003, USA.
authors.forename: Satendra
authors.initials: S
authors.lastname: Prasad
authors.forename: Hartwig
authors.initials: H
authors.lastname: Schmidt
authors.forename: Peter
authors.initials: P
authors.lastname: Lampen
authors.forename: Mei
authors.initials: M
authors.lastname: Wang
authors.forename: Robert
authors.initials: R
authors.lastname: Güth
authors.forename: Jaya V
authors.initials: JV
authors.lastname: Rao
authors.forename: Geoffrey B
authors.initials: GB
authors.lastname: Smith
authors.forename: Gary A
authors.initials: GA
authors.lastname: Eiceman
mesh_terms: D001419:Bacteria / Q000302:isolation & purification*; D015415:Biomarkers / Q000032:analysis; D002849:Chromatography, Gas / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods*; D008832:Microchemistry / Q000379:methods; D025341:Principal Component Analysis
chemical_list: D015415:Biomarkers