Curie-point Pyrolysis Mass Spectrometry Applied to Characterization and Identification of Selected Bacillus Species

Abstract

The use of pyrolysis mass spectrometry in the characterization and identification of Bacillus spp. was studied. Fifty-three strains of 4 closely related groups, B. subtilis, B. pumilus, B. licheniformis and B. amyloliquefaciens, were used in a study of both sporulated and non-sporulated cultures. Pyrolysis was carried out using a Pyromass 8-80, a novel pyrolysis mass spectrometer specifically designed for fingerprinting complex samples. The pyrolysis data obtained were analyzed using multivariate statistical techniques. All 4 groups could be differentiated using data from non-sporulated cultures, but the data from sporulated cultures did not separate B. subtilis from B. amyloliquefaciens or B. pumilus. B. licheniformis was more clearly differentiated from the other 3 spp. using these data. Culture maturity affected the mass spectra obtained from non-sporulated cultures.