Premium
Natural isolates of Bacillus thuringiensis display genetic and psychrotrophic properties characteristic of Bacillus weihenstephanensis
Author(s) -
Bartoszewicz M.,
Bideshi D.K.,
Kraszewska A.,
Modzelewska E.,
Swiecicka I.
Publication year - 2009
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1111/j.1365-2672.2009.04166.x
Subject(s) - library science , computer science
Abstract Aim: To determine the potential of Bacillus thuringiensis , known primarily for its entomopathogenicity, to be a psychrotolerant contaminant of stored products. Methods and Results: We determined the genetic properties and diversity of cold‐adapted isolates of B. thuringiensis based on (i) the presence of cspA , a genetic determinant that confers psychrotolerance in Bacillus weihenstephanensis , (ii) 16S rRNA genes, and (iii) pulse‐field gel electrophoretic (PFGE) genome profiles. We assessed the pathogenic potential of these isolates based on whether they harboured various combinations of known toxigenic‐associated determinants ( nheA , hblA , cytK ). Of 36 nonclonal B. thuringiensis cultured from soil and milk, 21 harboured cspA , and of these, 16 (76%) were psychrotolerant and possessed genetic signatures typical of psychrotrophic Bacillus species. The majority of psychrotolerant isolates contained various combinations of nheA , hblA , and cytK . Conclusion: Our results show that natural isolates of psychrotolerant B. thuringiensis occur in soil and milk, and suggest that psychrotolerance is determined by cspA . Significance and Impact of the study: The presence of cspA in combination with nheA , hblA , and cytK could be of concern if commercial products are contaminated with strains that harbour these determinants.