Are they involved in insecticidal activity in Bacillus thuringiensis?
Bacillus thuringiensis (Bt) is a gram-positive aerobic and facultative anaerobic endospore-forming bacterium found in the environment and is widely used as a biopesticide. B. thuringiensis belongs to the B. cereus group. Members of this group are known to produce emetic and enterotoxins that have been implicated as the causal agents for emetic and diarrhial syndromes. PCR and Southern hybridization were used to screen commercial B. thuringiensis products (ForayTM 48B, XenTariTM WD6, VecTobacTM and NovodorTM) that are used in Canadian agriculture and forestry for the presence of known and putative B. thuringiensis virulence factors. With the exception of cytotoxin-CytK gene, all the enterotoxin genes tested were present in the commercial products used in this study. In vivo expression of these genes is being evaluated in spruce budworm, Choristoneura fumiferana, gypsy moth, Lymantria dispar and colorado potato beetle, Leptinotarsa decemlineata.
