title: Polyphasic characterization of Bacillus species from anthrax outbreaks in animals from South Africa and Lesotho.
abstract: BACKGROUND
  Bacillus anthracis is the causative agent of anthrax, a disease endemic in regions of Northern Cape Province and Kruger National Park of South Africa. Accurate identification of virulent B. anthracis is essential but challenging due to its close relationship with other members of B. cereus group. This study characterized B. anthracis and Bacillus species that were recovered from animals and the environment where animals died of anthrax symptoms in southern Africa using a polyphasic approach.
  
  
  METHODS
  For this purpose, 3 B. anthracis and 10 Bacillus isolates were subjected to microbiology tests, BiologOmniLog identification system (Biolog), 16S ribosomal RNA (rRNA) sequence analysis, polymerase chain reaction (PCR) detection of protective antigen (pag) and capsule (cap) regions, and real-time PCR using hybridization probes targeting chromosomal, pag, and capC genes.
  
  
  RESULTS
  The Bacillus isolates were non-hemolytic, non-motile, and susceptible to penicillin, which is typical of B. anthracis, but resistant to gamma phage, unlike typical B. anthracis. The Biolog system and 16S rRNA gene sequence analysis identified most of the Bacillus isolates as B. endophyticus (7 of 10). Conventional PCR revealed that most of the Bacillus isolates contained capBCA gene regions. This highlights the limitation of the specificity of conventional PCR and the fact that the real-time PCR is more specific and reliable for anthrax diagnosis.
  
  
  CONCLUSIONS
  Real-time PCR, 16S rRNA sequencing, and confirmatory microbiology tests including phage resistance distinguished Bacillus isolates from B. anthracis in this study. Identification of B. anthracis should be done using a polyphasic approach.
authors: The Biotechnology Platform, Agricultural Research Council, Onderstepoort, South Africa. LekotaE@gmail.com.
authors: Kgaugelo Edward
authors: KE
authors: Lekota
authors: Ayesha
authors: A
authors: Hassim
authors: Joseph
authors: J
authors: Mafofo
authors: Jasper
authors: J
authors: Rees
authors: Farai Catherine
authors: FC
authors: Muchadeyi
authors: Henriette
authors: H
authors: Van Heerden
authors: Evelyn
authors: E
authors: Madoroba
mesh_terms: D000818:Animals; D000881:Anthrax / Q000453:epidemiology / Q000662:veterinary*; D000942:Antigens, Bacterial / Q000235:genetics; D001408:Bacillus anthracis / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D016667:Bacterial Capsules / Q000235:genetics; D001427:Bacterial Toxins / Q000235:genetics; D015373:Bacterial Typing Techniques; D016000:Cluster Analysis; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D004196:Disease Outbreaks; D004783:Environmental Microbiology; D007927:Lesotho / Q000453:epidemiology; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013019:South Africa / Q000453:epidemiology
chemical_list: D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; C030325:anthrax toxin