By comparing the energy metabolism differences between the cell growth phase and curdlan production phase, especially the differences in energy dissipation, the metabolic pathways of curdlan biosynthesis in Agrobacterium sp. ATCC 31749 was constructed. The differences in energy metabolism and its influencing factors were investigated. By using molecular biology techniques and bioinformatics tools, the electron respiratory chains in Agrobacterium sp. were constructed. A novel bioprocess involving high-density cell growth and high-productivity curdlan production was developed. Low C/N nutrition condition in the first fermenter was suitable for rapid cell growth. The cells in the first fermenter were diluted into the second fermenter to stimulate high productivity of curdlan under high C/N nutritional condition. A novel bioreactor for high viscous fermentation in industrial scale was developed. The mass transfer, mixing, and rheological behavior characteristics in gellan solution were investigated. A novel bioreactor was scaled up to 50m3 and was applied to gellan fermentation in commercial bioprocess.