Why Bt Toxins dont kill the bacteria itself??

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Bt-Toxin is an insectisidal protein produced by Bacillus thuringiensis  genome which is used in genetical engineering for making  Transgenic  Pest-resistant crop variety . The toxin  protein encoded by cry-gene exists as inactive protoxins in the bacterial cells ,which only gets activated when it is taken by insects in their Gut , The alkaline PH of the gut activates it ......This is the reason For that the bacteria do not harmed by  Bt-toxins .

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