Identification of a Bacillus strain producing alkaline protease

A protease producing spore-forming strain named HFBL0079 was islated from soil by measuring clearing zone in alkaline casein plate.Bacillus sp.HFBL0079 was identified as B.amyloliquefaciens by phenotypic properties and 16S rDNA sequence.Its optimal growth temperature was 35 °C-37 °C and initial pH was 8.0.Protease activity increased quickly in log phase in accord with biomass and was steady in stationary phase,the maximal value was found in 16 hours.The highest protease activity was found when nitrogen source was soy protein isolate.The protease was alkaline protease because the highest activity was shown in pH 10.The alkaline protease was shown activity to multi substrate,the highest hydrolysis degree was found in collagen(42.3%) more than casein,oval bumin,BSA,and the hydrolysis degree of keratin was 15.3%,these results indicated the alkaline protease had some novel properties.