Mutations in the regulatory regions result in increased streptomycin resistance and keratinase synthesis in Bacillus thuringiensis

Keratinases are a group of proteases of great industrial significance. To take full advantage of Bacillus species as an inherent superior microbial producer of proteases, we performed the ribosome engineering to improve the keratinase synthesis capacity of the wild-type Bacillus thuringiensis by inducing streptomycin resistance. Mutant Bt(Str-O) was identified as a stable keratinase overproducer. Comparative characterization of the two strains...