Isolation and characterization of protease producing Chryseobacterium indologenes strain BYK27 from Kerman,s dairy industry sewage

Proteases are one of the most important groups of industrial enzymes, constituting 65% of worldwide industrial enzyme marketing and around 25% of the total global enzyme production. Their use encompasses a great number of applications in different industrial sectors, such as detergent additives, in waste treatment processes, silver recovery and the food, leather, photographic and pharmaceutical industries. Protease producing bacteria were isolated from Kerman,s dairy industry sewage with clear zone surrounding colony in Skimmed milk agar plate. Its biochemically tests and 16S rRNA gene sequencing showed that it is Chryseobacterium indologenes strain BYK27. The extracellular protease secreted by this strain partially purified by a combination of ammonium sulfate precipitation, dialysis in Tris-HCl buffer 35 mM and ion-exchange chromatography. The temperature and pH optima for activity of produced protease were 40˚C, pH 8 and for stability were 40˚C, pH 8-9. This enzyme was activated by K, Triton X-100 and commercial detergent Tage. It was also active in 1% concentration of salinity. These results showed that protease BYK27 can be used in detergent industry, meat tenderization and peptide synthesis.