title: Virulence plasmid stability in environmentally occurring Bacillus anthracis from North East Turkey.
abstract: The Bacillus anthracis virulence plasmid pXO2, which encodes for a polypeptide capsule, can be lost during long term laboratory storage. To determine if pXO2 is lost in nature we screened B. anthracis isolates obtained from B. anthracis spores from contaminated animal burial sites in Turkey for their ability to express a capsule upon primary culture. A total of 672 B. anthracis colonies were examined of which ten produced a mixed mucoid (capsule +ve)/non-mucoid (capsule -ve) phenotype and a further one colony yielded non-mucoid colonies upon repeated culture. Screening by PCR using pXO2 specific primers revealed that seven of these isolates had eliminated the plasmid. Of the four colonies which were positive by PCR, one regained the ability to express a capsule upon repeated culture suggesting that the defect was reversible. This is an important observation as capsule expression is a principal marker of virulence and in the absence of PCR serves as a key diagnostic marker. The results of this preliminary study suggest that pXO2 is lost in nature and that further studies are need to determine the mechanisms by which this occurs.
authors.affiliation: Cardiff School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, CF10 3NB, Wales, UK.|Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91, Stockholm, Sweden.
authors.forename: Callum
authors.initials: C
authors.lastname: Cooper
authors.affiliation: Department of Microbiology, Faculty of Veterinary Medicine, University of Kafkas, 36100, Kars, Turkey.
authors.forename: Fatih
authors.initials: F
authors.lastname: Buyuk
authors.affiliation: Cardiff School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, CF10 3NB, Wales, UK.
authors.forename: Bettina
authors.initials: B
authors.lastname: Schelkle
authors.affiliation: Department of Microbiology, Faculty of Veterinary Medicine, University of Kafkas, 36100, Kars, Turkey.
authors.forename: Aliye Gulmez
authors.initials: AG
authors.lastname: Saglam
authors.affiliation: Department of Microbiology, Faculty of Veterinary Medicine, University of Kafkas, 36100, Kars, Turkey.
authors.forename: Elif
authors.initials: E
authors.lastname: Celik
authors.affiliation: Department of Microbiology, Faculty of Veterinary Medicine, University of Kafkas, 36100, Kars, Turkey.
authors.forename: Ozgur
authors.initials: O
authors.lastname: Celebi
authors.affiliation: Department of Microbiology, Faculty of Veterinary Medicine, University of Kafkas, 36100, Kars, Turkey.
authors.forename: Mitat
authors.initials: M
authors.lastname: Sahin
authors.affiliation: Defence Science and Technology Laboratory, Porton Down, Salisbury, UK.
authors.forename: Tom
authors.initials: T
authors.lastname: Hawkyard
authors.affiliation: Cardiff School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, CF10 3NB, Wales, UK. bailliel@cardiff.ac.uk.
authors.forename: Les
authors.initials: L
authors.lastname: Baillie
mesh_terms: D000818:Animals; D000835:Animals, Wild / Q000382:microbiology*; D000881:Anthrax / Q000382:microbiology / Q000662:veterinary*; D001408:Bacillus anthracis / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism / Q000472:pathogenicity*; D004783:Environmental Microbiology; D010957:Plasmids / Q000235:genetics* / Q000378:metabolism; D014421:Turkey; D014774:Virulence
keywords: Bacillus anthracis; Environmental; Plasmid stability