4. What are Cry proteins? Name an organism that produces it. How has man exploited this protein to his benefit?
Cry proteins are toxin protein encoded by cry genes. These are produced by a bacteria named Bacillus thuringiensis which itself remain safe from cry toxins by having methylated DNA. Cry proteins act as insecticides as they are toxic to insects. This property of Cry proteins has been exploited in producing genetically modified crops such as Bt cotton, Bt brinjal etc. These crops are resistant to insects of order Lepidoptera.