{Reference Type}: English Abstract {Title}: [Optimization of the fermentative production of L-methionine by engineered Escherichia coli]. {Author}: Niu K;Mei Z;Guan A;Cai W;Chen M;Liu Z;Zheng Y; {Journal}: Sheng Wu Gong Cheng Xue Bao {Volume}: 40 {Issue}: 3 {Year}: 2024 Mar 25 暂无{DOI}: 10.13345/j.cjb.230388 {Abstract}: As the only essential amino acid containing elemental sulphur, L-methionine has important physiological and biochemical functions in living organisms. However, the fermentative production of L-methionine has not met the requirements of industrial production because of its low production level. In this paper, the fermentation process of an efficient L-methionine producing strain E. coli W3110ΔIJAHFEBC trc-fliY trc-malY/PAM glyA-22 metF constructed previously was systematically optimized. Based on the optimal initial glucose concentration, the effects of different fed-batch fermentation processes, including DO-Stat, pH-Stat, controlling residual sugar control at different level and feeding glucose with constant rate, on L-methionine fermentation were studied. It was found that the control of glucose concentration greatly affected the fermentation process. Subsequently, an optimal fed-batch fermentation process was developed, where the L-methionine titer was increased to 31.71 g/L, the highest yield reported to date, while the fermentation time was shortened to 68 h. Meanwhile, a fermentation kinetics model under the optimal fed-batch fermentation conditions was established, which fitted well with the biosynthesis process of L-methionine. This study may facilitate further development of the fermentative production of L-methionine.