title: GC/MS method for positive detection of Bacillus anthracis endospores.
abstract: A simple method was developed for detection of Bacillus anthracis (BA) endospores and for differentiation of them from other species in the Bacillus cereus group. Chemical profiles that include lipids (i.e., fatty acids), carbohydrates (i.e., sugars), and the spore-specific biomarker, dipicolinic acid, were generated by one-step thermochemolysis (TCM) at 140 °C in 5 min to provide specific biomarker signatures. Anthrose, which is a biomarker characteristic of the B. cereus group of bacteria, was determined from a fragment produced by TCM. Surprisingly, several virulent BA strains contained very low levels of anthrose, which confounded their detection. A statistical discrimination algorithm was constructed using a combination of biomarkers, which was robust against different growth conditions (medium and temperature). Fifteen endospore-forming Bacillus species were confirmed in a statistically designed test (~90%) using the algorithm, including six BA strains (four virulent isolates), five B. thuringiensis (BT) isolates, and one isolate each for B. cereus (BC), B. mycoides (BM), B. atrophaeus (BG), and B. subtilis (BS). The detection limit for B. anthracis was found to be 50,000 endospores, on the basis of the GC/MS detection limits for 3-methyl-2-butenoic acid methyl ester, which is the biomarker derived from TCM of anthrose.
authors.affiliation: Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA.
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.forename: Tai V
authors.initials: TV
authors.lastname: Truong
authors.forename: Teri M
authors.initials: TM
authors.lastname: Bills
authors.forename: Brian C
authors.initials: BC
authors.lastname: Holt
authors.forename: Douglas N
authors.initials: DN
authors.lastname: VanDerwerken
authors.forename: John R
authors.initials: JR
authors.lastname: Williams
authors.forename: Abhilasha
authors.initials: A
authors.lastname: Acharya
authors.forename: Richard A
authors.initials: RA
authors.lastname: Robison
authors.forename: H Dennis
authors.initials: HD
authors.lastname: Tolley
authors.forename: Milton L
authors.initials: ML
authors.lastname: Lee
mesh_terms: D000465:Algorithms; D001407:Bacillus / Q000378:metabolism; D001408:Bacillus anthracis / Q000378:metabolism*; D015415:Biomarkers / Q000032:analysis; D002241:Carbohydrates / Q000032:analysis; D005227:Fatty Acids / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D010848:Picolinic Acids / Q000032:analysis; D013171:Spores, Bacterial / Q000378:metabolism
chemical_list: D015415:Biomarkers; D002241:Carbohydrates; D005227:Fatty Acids; D010848:Picolinic Acids; C004860:dipicolinic acid