[Preliminary study of P19 gene from Bacillus thuringiensis subsp israelensis]

The P19 gene and cyt1A gene were obtained by PCR with 9.7 kb HindIII fragment containing P19 gene and cyt1A gene from 72 MD plasmid of Bt as a template. Digested PCR products were ligated to expression vector pUHE24 and transformed into E. coli XL-1. Three clones, LZ19 harboring P19 gene, LZcyt1A harboring cyt1A gene, LZ19A harboring P19 gene and cyt1A gene, were screened. The growth cure of cloned strains were determined under IPTG induction. The result showed that pLZ19 did not affect the growth of E. coli, pLZcyt1A is typically Lethal for E. coli, Lethal initial efficiency of pLZ19A is much higher than that of pLZcyt1A. Probably, this was a result that P19 gene enhanced initial expression of cyt1A gene in E. coli.