Overexpression of the Bacillus licheniformis GroES enhances thermotolerance of Bacillus subtilis WB600

Abstract

Use of thermotolerant strains offers the advantage of conducting production process at elevated temperatures, thereby improving the catalytic efficiency and reducing the energy consumption and the production costs. In the present study, thermotolerance gene groES from the thermophilic strain Bacillus licheniformis B186 was implanted into B. subtilis WB600 to improve its thermotolerance. The engineered strain WB600-pHY-groES displayed reduced doubling time as well as increased specific growth rates and cell viability compared with the control. Our results suggested that introducing heat shock proteins (HSPs) from thermophiles into B. subtilis could be an effective approach to enhance its thermotolerance, thus facilitating the development of multichaperone expression systems for constructing more thermotolerant commercial B. subtilis strains. To the best of our knowledge, this is the first report on improving the thermotolerance of B. subtilis by overexpression of HSPs.

Keywords

• GroES
• thermotolerance; Bacillus subtilis
• heat shock protein