Bacillus cereus produces several nonproteinaceous insecticidal exotoxins

Bacillus cereus is mainly known as a human food-borne opportunistic pathogen. Here, we used biological assays and HPLC to investigate the ability of B. cereus to produce insecticidal exotoxins during the stationary growth phase. None of the 575 B. cereus strains screened produced detectable levels of B-exotoxin 1, a small, heat-stable insecticidal nucleotide analogue. However, six out of a subset of 270 B. cereus strains produced several small, nonproteinaceous insecticidal exotoxins different from beta-exotoxin 1. Thus, B. cereus can secrete a large array of proteinaceous and nonproteinaceous toxins acting on insects and mammals. (c) 2005 Elsevier Inc. All rights reserved.