Isolation of a thermostable alkaline cellulase-producing bacterium strain from a garbage dump

Abstract

Thermostable alkaline cellulases can resist high temperature and high pH, which make them widely applicable in the industries of food, detergent, paper making, and biomass utilization. To obtain favorite thermostable alkaline cellulaseproducing bacterial strains, these bacteria were isolated from collected soil and plant putrefaction samples in long-term garbage dumps. One bacterium strain from lime-applied garbage dumps, named as SWU-27, was picked up since its crude enzyme showed stronger activities of cellubiohydrolase, endoglucanase, and β-glucosidase. All these activities could tolerate the treatment of high temperature (up to 80°C) and endoglucanase and β-glucosidase activities could even tolerate high pH (over 10). Taxonomic study showed that strain SWU-27 is another geographic strain of Gram-negative Klebsiella pneumoniae. In conclusion it is suggested that lime-applied dumps are preferable places to isolate novel thermostable alkaline cellulaseproducing bacterial strains.