Preventing infections in patients undergoing surgical procedures is a primary goal for all members of the healthcare team. This is especially important in today’s dynamic healthcare environment, in the face of newly recognized pathogens, well­known microorganisms that have become resistant to treatment modalities, and the economic pressures to reduce. Healthcare­associated infections. A key infection control practice for reducing the likelihood of a surgical site infection is proper reprocessing of surgical instruments. In its 2008 Guideline for Disinfection and Sterilization in Healthcare Facilities, the Centers for Disease Control and Prevention (CDC) notes that failure to properly disinfect and sterilize equipment carries not only the risk associated with breach of host barriers, but also the risk for person­to­person transmission as well as transmission of environmental pathogens; furthermore, thorough cleaning is required before disinfection and sterilization because inorganic and organic materials that remain on the surfaces of instruments interfere with the effectiveness of these processes. Proteases are the most important type of enzyme to look for when choosing an enzymatic detergent for medical use because there is a high content of protein in most body fluids (including blood, tissue and mucous) which cannot be easily removed with regular detergents/surfactants and water, proteases break down protein into individual amino acids or short string of amino acid. Amino acid and peptides are much more soluble in water and will float away the surface of the instrument. In the present study the slaughterhouse drainage sample collected was screened for presence of bacteria, which can utilize blood protein as their protein source. The samples were serially diluted on blood agar. From these plates, depending upon their morphological, microscopical and physiological characters, the isolates were suspected to be Bacillus cereus. The colonies were confirmed by cultivating on selective media. On PEMBA (Polymyxin pyruvate egg­yolk mannitol bromothymol blue agar) media the isolated colonies were peacock blue in colour. This confirms the presence of Bacillus cereus. The isolates have been designated as Bacillus cereus KLM1, KLM2, KLM3 and KLM4. Of these KLM4 isolate was chosen as potential producer of protease enzyme depending upon its zone of lysis on fibrin plates and studied further for production of protease enzyme and its compatibility for the use of enzymatic detergent preparation for the cleaning surgical instruments.

Keywords: Protease; Zymography; Bacillus Cereus KLM4