Gas chromatographic-mass spectrometric determination of muramic acid content and pyrolysis profiles for a group of gram-positive and gram-negative bacteria

Abstract

Two gas chromatographicmass spectrometric methods, one based on chemical derivatisation and the other on analytical pyrolysis, were employed for the characterisation of a diverse group of bacteria. The muramic acid content of some Gram-positive and Gram-negative bacteria (including legionellae) was determined by aldononitrile acetate derivativisation and capillary GC -MS analysis. Muramic acid levels were generally higher in Gram-positive than in Gram-negative bacteria. When applied to the same set of bacteria, pyrolysis GC -MS and non-linear mapping were also able to distinguish Gram-negative from Gram-positive bacteria. The potential of GC -MS techniques for the direct chemical characterisation of bacteria is discussed.

Variations in Soil Microbial Communities and Residues Along an Altitude Gradient on the Northern Slope of Changbai Mountain, China

“…Disparities might be explained if other methods determining microbial community composition at higher resolution were included, such as ribosomal RNA gene based analysis [24]. The lower Gm + /Gm − ratio in this site probably contributed to its higher GluN/MurA ratio because cell wall of Gm − bacteria contains thinner murein layers than that of Gm + bacteria, leading to lower MurA concentrations in living Gm − than Gm + bacteria [48], [49].…”

Microbial lipid and amino sugar responses to long-term simulated global environmental changes in a California annual grassland

“…In addition, the dominant amino sugars might be decomposed as a type of N nutrient for plant and microbial growth under warming and extreme nutrient-limited conditions. The distinct increase in MurA under treatments could be explained by faster bacterial life cycles associated with faster turnover rate, or a bacterial community shift from Gm - to Gm + bacteria which contain thick murein layers ( Eudy et al, 1985 ; Kogel-Knabner, 2002 ).…”

Speciation of Listeria via pyrolysis/gas chromatography

“…Several studies have shown that bacteria can be differentiated by Gram type utilizing pyrolysis [7,8]. Examination of the peptidoglycan pyrolysis product, acetamide, can also assist in Gram typing of organisms [9][10][11][12] by pyrolytic analysis. Differentiation of bacteria based upon the relative amounts of furfuryl alcohol and acetamide has also been studied [13].…”