Improving the thermoactivity and thermostability of pectate lyase from Bacillus pumilus for ramie degumming.

摘要: Thermostable alkaline pectate lyases can be potentially used for enzymatically degumming ramie in an environmentally sustainable manner and as alternative to the currently chemical-based processes. To assess its potential applications, lyase from Bacillus pumilus (ATCC 7061) was cloned expressed Escherichia coli. Evolutionary strategies were applied generate efficient enzymes. Obtained site-saturation mutagenesis random mutagenesis, best performing mutant enzyme M3 exhibited a 3.4-fold higher specific activity on substrate polygalacturonic acid, compared with wild-type enzyme. Furthermore, half-life of inactivation at 50 °C extended over 13 h. In contrast, completely inactivated less than 10 min under same conditions. An upward shift optimal reaction temperature mutant, 75 °C, observed, which that Kinetic parameter data revealed catalysis efficiency Ramie also demonstrated more Collectively, our results suggest remarkable improvements thermoactivity thermostability, has applications textile industry.