Differential Expression of Xylanases and Endoglucanases in the Hybrid Derived from Intergeneric Protoplast Fusion between a Cellulomonas sp. and Bacillus subtilis.

A stable hybrid obtained by protoplast fusion between a Cellulomonas sp. and Bacillus subtilis exhibits an altered pattern of enzyme induction with different cellulosic substrates. Unlike in the Cellulomonas sp., xylanase was induced in the hybrid organism specifically by xylan, and endoglucanase was induced by carboxymethyl cellulose. The amount and specific activity of xylanase produced by the hybrid were more than those produced by the Cellulomonas sp. beta-Glucosidase which is cell bound or intracellular in the Cellulomonas sp. was secreted by the hybrid organism, and relative amounts of extracellular beta-glucosidase were high. Furthermore, this extracellular beta-glucosidase activity was dependent on the nature of the cellulosic substrate. Endoglucanases synthesized in the hybrid differed in their electrophoretic mobilities as compared with the parental enzymes.