Alkaline thermostable and halophilic endoglucanase from Bacillus licheniformis C108

Abstract

An endoglucanase was purified from halophilic alkaline Bacillus  licheniformis isolated from soils of Lake Van in Turkey. The optimal pH and temperature of the endoglucanase produced by B.licheniformis C108 were 10.0 and 30°C, respectively. The enzyme was highly stable up to 100°C at pH 10.0 and the enzyme retained its complete activity for 6 h in 7 to10% of NaCl. The activity of the enzyme was significantly inhibited by sodium dodecyl sulfate (SDS), Triton X-100, zinc chloride (ZnCl2),
phenylmethanesulfonylfluoride (PMSF) and Urea. The partially purified enzyme revealed that, products of carboxymethylcellulosic hydrolysis were glucose, cellobiose and other longer cellooligosaccharides. Thermostability, alkalinity, halostability and high hydrolytic capability make this enzyme a potential candidate for environmental bioremedetion and bioethanol production processes from cellulosic biomasses as well as waste treatment processes.

Key words: Cellulose, Bacillus licheniformis, CMCase, endoglucanase, halostable.