Microbial proteases account for approximately 40% of the total worldwide enzyme sales and most of the commercial proteases are of bacterial origin. So planned to screen out bacterial cultures from various sources producing significant amount of alkaline proteases. Samples collected were serially diluted and plated on skim milk agar plates and incubated at 37 ºC for 3-4 days to allow the colonies to grow. Zone of clearance of casein surrounding the colony has provided a measure of their Proteolytic activity. The isolates showing zone of casein hydrolysis on milk agar plates were studied for their relative enzyme activity (REA) on skim milk agar plate. To compare the caseinolytic activity of enzyme produced, the isolates were inoculated in production medium and put on an environmental shaker at 100 rpm at 37ºC for 168 hours and checked for enzyme activity at interval of 24 hours. Selected isolateB-4 was studied for cultural, morphological, biochemical   characteristics and identified by 16S rRNA sequencing and also employed for optimization of cultural conditions and components of production medium. We also employed the crude enzyme for its efficiency of gelatin hydrolysis and silver extraction from used X-ray films.

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