P142: Metabolic evolution of Mannheimia succiniciproducens for the succinate production and its proteomic characteristics

Mannheimia succiniciproducens utilizes sucrose as a carbon source for the production of succinate. To improve the cell growth and volumetric productivity of succinate, a combined strategy of metabolic engineering and evolutionary engineering was introduced. Recently identified sucrose utilization system in M. succiniciproducens  was composed of sucrose phosphotransferase (PTS), sucrose 6-phosphate hydrolase, and fructose (PTS). The sucrose 6-phosphate hydrolase that has crucial role in utilization of sucrose hydrolyzing sucrose 6-phosphate into glucose 6-phosphate and fructose was overexpressed to improve the rate of sucrose utilization. The overexpression of sucrose 6-phosphate hydrolase followed by adaptive evolution under the growth-maximized condition increased specific growth rate and productivity of succinate. Particularly, the evolved strain fermented mixed sugars more rapidly than the parent strain. In addition, comparative proteome analysis was carried out to uncover metabolic characteristics of this evolved strain. [This work was supported by the Advanced Biomass R&D Center (ABC) of Korea Grant funded by the Ministry of Education, Science and Technology (2010-0029799). Further supports by the World Class University Program (R32-2008-000-10142-0) of the MEST were appreciated.]