Improvement of L-Valine Production at High Temperature in Brevibacterium flavum by Over-expressed ilvEBNrC genes
Brevibacteriumflavum ATCC14067 was engineered for L-valine production by over-expression of the ilvEBNrC genes from B.flavum NV128.In traditional fermentation,L-valine production reached 30.08±0.92 g/L at 31℃ in 72 h with a low conversion efficiency of 0.129 g/g.To further improve the L-valine production and conversion efficiency,based on the optimum temperatures of L-valine biosynthesis enzymes (above 35℃) and the thermotolerance of B.flavum,the fermentation temperature was enhanced to 40℃.As a result,maximum L-valine production,conversion efficiency and specific L-valine productivity reached 38.08 ±1.32 g/L,0.241 g/g and 0.133 g/g/h respectively at 37℃ in 48h fermentation.The strategy for enhancing L-valine production with over-expression key enzymes in thermotolerance strain may provide an altemative approach to enhance branchedchain amino acids production with other strains.
Brevibacterium flavum L-valine high temperature fermentation
Xiaohu Hou He Qian Weiguo Zhang
The Key Laboratory of Industrial Biotechnology,Ministry of Education,School of Biotechnology,JiangNa The State Key Laboratory of Food Science and Technology,School of Food Science,JiangNan University,P
国内会议
南京
英文
171-182
2011-08-12（万方平台首次上网日期，不代表论文的发表时间）