title: Killing the spores of Bacillus species by molecular iodine.
abstract: OBJECTIVE
  To determine the responses of spores of Bacillus subtilis and Bacillus anthracis surrogate Bacillus thuringiensis Al Hakam to I2treatment.
  
  
  RESULTS
  Spores of B. subtilis and B. thuringiensis killed by aqueous 30°C-I2could germinate, and their inner membrane (IM) was intact. Spore coats were important in I2resistance, DNA-protective proteins were not important, and survivors of I2treatment were not mutagenized. Viabilities of I2-treated, 90-98% killed spores were much lower on high-salinity media, and the treated spores were more heat sensitive than the untreated spores. Germinated I2-killed spores were dead as determined by staining with nucleic acid dyes, and many appeared to have been lysed.
  
  
  CONCLUSIONS
  Aqueous I2appeared to kill B. subtilis and B. thuringiensis spores such that spores lyse soon after they germinate, and not by causing DNA damage or rupture of spores' IM. I2treatment also generated many damaged spores that could only be recovered under nonstressful conditions.
  
  
  CONCLUSIONS
  This work shows that spores of the model organism B. subtilis, and B. thuringiensis, a surrogate for B. anthracis spores, exhibit similar mechanisms of resistance to and killing by I2. Generation by I2treatment of conditionally dead spores indicates that appropriate media are essential to efficiently enumerate viable I2-treated spores.
authors.affiliation: Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, USA.
authors.forename: Q
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, USA.
authors.forename: G
authors.initials: G
authors.lastname: Korza
authors.affiliation: Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, USA.
authors.forename: P
authors.initials: P
authors.lastname: Setlow
mesh_terms: D001407:Bacillus / Q000187:drug effects* / Q000502:physiology; D001408:Bacillus anthracis / Q000187:drug effects / Q000502:physiology; D001412:Bacillus subtilis / Q000187:drug effects / Q000502:physiology; D004249:DNA Damage; D006358:Hot Temperature; D007455:Iodine / Q000494:pharmacology*; D013171:Spores, Bacterial / Q000187:drug effects* / Q000502:physiology
chemical_list: D007455:Iodine
keywords: 
  Bacillus
  ; bacterial spores; biocides; disinfection; iodine; spores