Faculty of Biotechnology and Food Sciences in Nitra Journal of Microbiology, Biotechnology and Food Sciences 1338-5178 no. 5 vol. 6 2017-04-03 2017-04-03 MICROWAVE MUTAGENESIS OF BREVIBACILLUS PARABREVIS FOR ENHANCED CELLULASE PRODUCTION, AND INVESTIGATION ON THERMOSTABILITY OF THIS CELLULASE 1213 1217 EN Pinakin Khambhala Pinakin Khambhala Purva Paliwal Purva Paliwal Vijay Kothari Vijay Kothari Microwave mutagenesis of Brevibacillus parabrevis for enhanced cellulase production was attempted. Though microwave treatment could alter the cellulase activity of the test bacterium, none of the mutants obtained were found to be genetically stable, indicating the reversible nature of microwave-induced mutation(s). Thermal stability of the B. parabrevis cellulase was also investigated. This enzyme was found to be capable of retaining its activity even after heat treatment (50-121ºC, for 30-60 min). Fluorescence spectrum revealed a red shift in the emission maxima of the heat-treated enzyme preparations, indicating some structural change upon heating, but no major loss of activity was observed. This enzyme was found to be active over a broad temperature range, with 90ºC as the optimum temp, which is interesting as the producing organism is a mesophile.