[Multiple genes of delta-endotoxins from Bacillus thuringiensis subspecies galleriae]

Cloning and expression in E. coli delta-endotoxin genes cryIAb7, cryIG and, cryIX from Bacillus thuringiensis ssp galleriae has been performed. Restriction mapping and partial sequencing have shown the identity of the 3'-terminal parts of cryIG and cryIX, although their 5'-terminal halves corresponding to the toxin are unique. Sequencing 5'-flanking region of cryIX revealed no translation initiation site, which indicates a nonfunctional state of the gene. The clusterized locating of the cryIG and cryIG genes has been shown. The absence of a promoter-like structure in the 5'-flanking region of cryIG suggests transcription of the gene as a bicistronic mRNA with cryIX. The extremely high homology of the cryIG and cryIX 3'-terminal parts (2 kB long) suggests a recombination act in the gene origin.