Determination of carbohydrate profiles of Bacillus anthracis and Bacillus cereus including identification of O-methyl methylpentoses by using gas chromatography-mass spectrometry

Abstract

BaciUus anthracis and BaciUus cereus are closely related pathogenic organisms that are difficult to differentiate phenotypically or genotypically. It is well known that vegetative and spore forms of bacilli are quite distinct both morphologically and chemically, but spore-specific chemical markers allowing these species to be distinguished have not been previously described. By using gas chromatography-mass spectrometry, vegetative cells and spores of the two species were shown to exhibit distinct carbohydrate profiles. Profiles of vegetative B. anthracis typically contained high levels of galactose but did not contain galactosamine, whereas B. cereus contained galactosamine and generally low levels of galactose. Spore cultures exhibited unique carbohydrate profiles compared with those of vegetative cultures. B. anthracis spore profiles contained rhamnose alone, whereas B. cereus spore profiles contained rhamnose and fucose. Additionally, two spore-specific 0-methylated methylpentoses were discovered. Both B. anthracis and B. cereus spores contained 3-0-methyl rhamnose, whereas B. cereus spores also contained 2-0-methyl rhamnose. Carbohydrate profiling is demonstrated to be a powerful tool for differentiating the two closely related species. Differentiation does not depend on whether organisms are in the vegetative or spore stage of growth.

Single cell profiling of surface carbohydrates on Bacillus cereus

“…Using two specific carbohydrate binding lectins, wheat germ agglutinin (WGA) and concanavalin A (Con A), as probes, we show that the carbohydrates N-acetylglucosamine (GlcNAc) and glucose/mannose (Glu/Man) can be detected, mapped and quantified on single entire bacterial cell surfaces at the nanoscale. The choice of these targets was dictated by several studies showing the heterogeneity and changes in aminosugar and simple sugars across different strains and species, making them critical targets for profiling [1,7,11,12]. We show that these carbohydrates can be measured in both vegetative and spore states in liquid environments.…”

“…Owing to their ability to form spores in response to nutrient deprivation conditions, the profiles of both vegetative cells and spores for these bacilli have been of great interest [11]. Changes in the surface carbohydrate compositions on B. anthracis and B. cereus were investigated as surface biochemical markers for tracking the spore-forming process [12]. To date, several techniques have been applied to analyse the bacterial surface carbohydrate compositions, primarily involving the use of gas chromatography-mass spectrometry (GC-MS), ion-exchange chromatography, gel chromatography and high-performance liquid chromatography [1,13,14].…”

Characterization of spore surfaces from a Geobacillus sp. isolate by pH dependence of surface charge and infrared spectra

“…As there are no stains for specific anionic groups, the images were interpreted with reference to previous studies (Driks 1999;Waller et al 2004). For example, it has been reported that the outer surface of the exosporium surrounding B. anthracis and Bacillus subtilis spores contains glycoproteins (Fox et al 1993;Fox et al 2003).…”

“…2004). For example, it has been reported that the outer surface of the exosporium surrounding B. anthracis and Bacillus subtilis spores contains glycoproteins (Fox et al. 1993; Fox et al.…”

Identification of Brucella by Ribosomal-Spacer-Region PCR and Differentiation of Brucella canis from Other Brucella spp. Pathogenic for Humans by Carbohydrate Profiles

“…There is clearly a need for further study of the carbohydrate contents of brucellae. Whole-cell carbohydrate profiling by gas chromatography-mass spectrometry (GC-MS) has proven successful in differentiating other closely related groups of organisms, including legionellae and bacilli (12,14,15,34).…”