earticle

영어

Protease (EC 3.4.21) catalyzes the cleavage of the peptide bonds in proteins, and it is found in a wide variety of microorganisms. The application of alkaline protease has increased in foods, leathers, pharmaceuticals, bioremediations, and textiles.1) Bacterial protease has become one of the largest classes of industrial enzymes, accounting for 60% of the total global enzyme sales.2) Microbial proteases represent a good source of enzymes due to their broad biochemical diversity, the rapid growth of microorganisms, the limited space for cultivation, and the easy manipulation of cells for the production of novel enzymes.This study aims to conduct purification and characterization of protease from Bacillus subtilis RKY3. The protease produced by B. subtilis RKY3 was purified in two steps including ammonium sulfate precipitation and anion exchange chromatography. Molecular weight of the purified protease was approximately 38 kDa. The purified protease was stable over a broad pH range from 5.0 to 11.0, and it exhibited a relatively high activity at a broad range of pH between 7.0 and 9.0. The optimum temperature for enzyme activity was 60℃, but the activity was sharply deactivated beyond 60℃. The purified protease was found to be serine protease because the enzyme activity was almost inhibited by 1 mM of PMSF. It was stable with oxidants (H2O2), reducing agents (SDS), and organic solvents (bezene, hexane, and toluene). The protease purified in this study has a possibility to be used in detergent and bleaching industries.