Expression and processing of a bacterial endoglucanase in transgenic mice

The C6.5 endoglucanase from Bacillus subtilis catalyzes the hydrolyses of beta-glucans. This enzyme, which is also produced by many ruminant microbes, is not part of the normal digestive repertoire of monogastric animals. We have generated transgenic mice which express the C6.5 endoglucanase gene specifically in the pancreas with secretion of the enzyme into the small intestine. The secreted enzyme has a molecular mass of 55 kDa which is reduced by protease digestion to the principal forms of 37 and 35 kDa. These truncated forms are resistant to further protease degradation and exhibit enhanced specific activity compared to the native enzyme. These results encourage further investigation of the utility of this transgene for enhancing the digestive capability of monogastric animals.