Production of α-Amylase Bacillus amyloliquefaciens in the Expression System of Bacillus mojavensis and Properties of the Recombinant Enzyme

The conditions of recombinant ɑ-amylase production in an induction-free cultivation system based on Bacillus mojavensis are described. Fermentation was carried out in pilot fermenters under deep cultivation, which ensured the production of experimental batches in the quantities necessary for comprehensive studies of the samples obtained. Gradual accumulation of the recombinant enzyme in the bioreactor reaches a maximum after 31 hours. Some biochemical parameters of the recombinant enzyme were studied. Its thermostability was established, and the pH optimum of activity manifestation was determined—the maximum efficiency of substrate hydrolysis was observed when the sample was preheated for 30 min at a temperature of 55°C and pH equal to 7.2. An inversely proportional relationship between the change in the level of amylolytic activity and the amount of calcium chloride added during cultivation was revealed. The possibility of creating strains producing recombinant ɑ-amylase on the basis of B. mojavensis strain BDV-1 was demonstrated.