Purification and characterisation of extracellular protease produced by Clostridium sp. from Schirmacher oasis, Antarctica

• Published in: Enzyme and microbial technology Vol. 36; no. 5; pp. 824 - 831
• Main Authors: Alam, S.I., Dube, Smita, Reddy, G.S.N., Bhattacharya, B.K., Shivaji, S., Singh, Lokendra
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.04.2005; Elsevier Science
• Subjects: Anaerobe; Antarctica; Biological and medical sciences; Biology of microorganisms of confirmed or potential industrial interest; Biotechnology; Clostridium; Clostridium subterminale; Fundamental and applied biological sciences. Psychology; Miscellaneous; Mission oriented research; Protease; Psychrotroph; Antarctica; Clostridium; Psychrotroph; Antarctica; Protease; Anaerobe; Purification; Enzyme; Clostridiales; Extracellular; Peptidases; Clostridiaceae; Bacteria; Hydrolases; Psychrotrophy
• ISSN: 0141-0229; 1879-0909
• DOI: 10.1016/j.enzmictec.2005.01.011

One anaerobic, proteolytic bacterium isolated from Schirmacher oasis, Antarctica was characterised taxonomically. Based on morphology, biochemical characteristics and 16S rRNA sequence the isolate was identified as Clostridium species with closest similarity with Clostridium subterminale. Isolate was psychrotrophic forming maximum cell mass between 5 and 10 °C and produced extracellular protease. Growth was observed in the pH range of 6.5–8.5 with optimum at pH 8. Protease was purified 12.7-fold with a total yield of 26.2%. Effect of temperature, pH and salt concentration on enzyme activity were studied. Protease was found to be a serine-type metaloenzyme, which is active in a broad range of pH. It was moderately thermolabile and resistant to SDS. Enzyme kinetics revealed a tendency to decrease K m with increase in temperature for casein substrate.