title: Raman spectroscopic study of bacterial endospores.
abstract: Endospores and endospore-forming bacteria were studied by Raman spectroscopy. Raman spectra were recorded from Bacillus licheniformis LMG 7634 at different steps during growth and spore formation, and from spore suspensions obtained from diverse Bacillus and Paenibacillus strains cultured in different conditions (growth media, temperature, peroxide treatment). Raman bands of calcium dipicolinate and amino acids such as phenylalanine and tyrosine are more intense in the spectra of sporulating bacteria compared with those of bacteria from earlier phases of growth. Raman spectroscopy can thus be used to detect sporulation of cells by a characteristic band at 1,018 cm(-1) from calcium dipicolinate. The increase in amino acids could possibly be explained by the formation of small acid-soluble proteins that saturate the endospore DNA. Large variations in Raman spectra of endospore suspensions of different strains or different culturing conditions were observed. Next to calcium dipicolinate, tyrosine and phenylalanine, band differences at 527 and 638 cm(-1) were observed in the spectra of some of the B. sporothermodurans spore suspensions. These bands were assigned to the incorporation of cysteine residues in spore coat proteins. In conclusion, Raman spectroscopy is a fast technique to provide useful information about several spore components.
authors.affiliation: Department of Analytical Chemistry, Ghent University, Proeftuinstraat 86, 9000, Ghent, Belgium.
authors.forename: Joke
authors.initials: J
authors.lastname: De Gelder
authors.forename: Patsy
authors.initials: P
authors.lastname: Scheldeman
authors.forename: Karen
authors.initials: K
authors.lastname: Leus
authors.forename: Marc
authors.initials: M
authors.lastname: Heyndrickx
authors.forename: Peter
authors.initials: P
authors.lastname: Vandenabeele
authors.forename: Luc
authors.initials: L
authors.lastname: Moens
authors.forename: Paul
authors.initials: P
authors.lastname: De Vos
mesh_terms: D001407:Bacillus / Q000737:chemistry / Q000145:classification / Q000254:growth & development; D001431:Bacteriological Techniques / Q000379:methods; D003470:Culture Media / Q000737:chemistry; D013059:Spectrum Analysis, Raman; D013171:Spores, Bacterial / Q000737:chemistry* / Q000145:classification / Q000254:growth & development
chemical_list: D003470:Culture Media