Quantitative pyrolysis gas chromatography-mass spectrometry of bacterial cell walls

Novel biomarkers for Gram-type differentiation of bacteria by pyrolysis–gas chromatography–mass spectrometry

“…Therefore, the composition of bacterial pyrolyzates has been studied for almost a half century using diverse analytical techniques to obtain characteristic 'fingerprints' of pyrolysis products and/ or to elucidate the identity and cellular origin of thermally generated compounds. The proposed origin of identified thermal degradation products observed during whole cell bacterial pyrolysis is usually validated by comparison with pyrolytic products generated from suitable model compounds or cell fractions pyrolyzed under identical conditions [1][2][3][4][5]. Pyrolysis products of cytosol components such as nucleic acids and proteins are composed of very similar compounds, and although used for pyrolytic typing of different strains, these thermally generated molecules do not provide enough biomarker information to distinguish bacterial species or even to differentiate between prokaryotic and eukaryotic organisms.…”

“…Acetamide was used for quantification of cell wall peptidoglycan [16]. In addition, Hudson et al [4] applied Py-GC-mass spectrometry (MS) to the Gram-typing of bacteria using levels of both acetamide and propionamide, which originates from the pyrolysis of the lactyl residue in a muramic acid component of peptidoglycan. Moreover, it is well established that Gram staining correlates also with many other metabolic processes, e.g., the biosynthesis of different type of fatty acids.…”

Speciation of Listeria via pyrolysis/gas chromatography

“…However, with the spread parameter increased to 2.0, the number of assignments increases to 23, 6 L. innocua, 6 L. ivanovii, no L. monocytogenes, and 11 L. seeligeri (all correct), with the rest being ''undefined''. This trend continues as the spread parameter is increased to 10 Several encouraging trends can be discerned from these plots. Of primary importance is the observation that as the spread parameter is increased, allowing the PNN to classify more of the input vectors, the number of correct classifications rises rapidly and the number of undefined classifications falls nearly as rapidly.…”

“…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].…”

Detection of microbial biomass in subseafloor sediment by pyrolysis⿿GC/MS

“…A number of characteristic pyrolysis fragments have been identified from different biological sources in previous work [6,10,11,15,25,26,27,29,30,31,32] as well as in this study (see details in Table 3). The pyrolysis fragments were usually generated from multiple biopolymers, except for acetamidoacetaldehyde (only detected from GlcNAc), 2picolinamide (only from peptidoglycan; Fig.…”