Identification of toxin genes encoding Cyt proteins from standard and Argentine strains of Bacillus thuringiensis

Abstract

Polymerase chain reaction-restriction fragment length polymorphism methods for identification of cyt subclasses from Bacillus thuringiensis were established. Eight of 68 standard and ten of 107 Argentine B. thuringiensis strains harbor at least one cyt gene. The combination of cyt1Aa/cyt2Ba genes was identified in four standard and in ten native strains, whereas the cyt1Ba, cyt2Aa and cyt2Bb genes alone and the cyt1Ab/cyt2Bc genes together were found in four different standard strains respectively. The cyt2Ba genes from three B. thuringiensis svar israelensis strains and two Argentine B. thuringiensis strains were cloned, sequenced and designated as cyt2Ba10 to cyt2Ba14 respectively. These results suggest that these methods are relevant tools for identification of toxin genes encoding Cyt proteins in B. thuringiensis.

Keywords: Bacillus thuringiensis, cyt1, cyt2, PCR-RFLP

J. Trop. Microbiol. Biotechnol. 8: 3-8