Hyper-production of insecticidal crystal protein (delta-endotoxin) by Bacillus thuringiensis var. israelensis is not related to sporulation-specific biochemical functions.
Hypertoxic mutant strains of Bacillus thuringiensis var. israelensis were isolated by mutagenesis of the parent strain. The correlation, if any, between hyper-production of insecticidal crystal protein (delta-endotoxin) by hypertoxic mutant strains of Bacillus thuringiensis var. israelensis and sporulation-specific biochemical functions was studied. No increase in sporulation-specific biochemical markers was observed in the hypertoxic mutant strains. Asporogenous mutants of hypertoxic mutant strains blocked at different stages of sporulation were isolated, and larvicidal activity was studied. The hypertoxic parent strains and the sporulation-deficient, hypertoxic mutant strains showed almost identical larvicidal activity. Therefore, the increased production of toxin is not related to sporulation-specific biochemical changes.
Malaria Research Center, 22, Sham Nath Marg, Delhi-110 054, India.
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Bhattacharya
D001413:Bacillus thuringiensis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000378:metabolism* / Q000494:pharmacology; D001427:Bacterial Toxins / Q000378:metabolism* / Q000494:pharmacology; D004731:Endotoxins / Q000378:metabolism* / Q000494:pharmacology; D005020:Ethyl Methanesulfonate / Q000494:pharmacology; D006460:Hemolysin Proteins; D007814:Larva / Q000187:drug effects; D016296:Mutagenesis; D013170:Spores
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis; D005020:Ethyl Methanesulfonate