In this study, the engineered E. coli was constructed for efficient transformation of glycerol to 1,3-propanediol (1,3-PDO). To regenerate NADPH, the key bottleneck in 1,3-PDO production, heterologous NADP⁺-dependent glyceraldehyde-3-phosphate dehydrogenase (GAPDN, encoded by gapN) pathway was introduced, and the gapN expression level was fine-tuned with specific 5′-untranslated regions (5′-UTR) to balance the carbon flux distribution between the metabolic pathways of NADPH regeneration and 1,3-PDO biosynthesis. Additionally, glucose was added to the medium to promote glycerol utilization and cell growth. To elevate the utilization of glycerol in the presence of glucose, E. coli JA11 was constructed through destroying PEP-dependent glucose transport system while strengthening the ATP-dependent transport system. Subsequent optimization of nitrogen sources further improved 1,3-PDO production. Finally, under the optimal fermentation condition, E. coli JA11 produced 13.47 g/L 1,3-PDO, with a yield of 0.64 mol/mol, increased by 325% and 100% compared with the original engineered E. coli JA03, respectively.

在这项研究中，构建了工程化的大肠杆菌以将甘油有效转化为1,3-丙二醇（1,3-PDO）。为了再生NADPH，在1,3-PDO生产中的关键瓶颈，异源NADP ⁺依赖性甘油醛-3-磷酸脱氢酶（GAPDN，由编码的gapN）通路被引入，并且的gapN表达水平与特异性5微调' -非翻译区（5'-UTR），以平衡NADPH再生代谢途径和1,3-PDO生物合成之间的碳通量分布。另外，将葡萄糖添加到培养基中以促进甘油的利用和细胞生长。在葡萄糖，大肠杆菌的存在下提高甘油的利用率JA11是通过破坏PEP依赖性葡萄糖转运系统，同时加强ATP依赖性转运系统而构建的。随后氮源的优化进一步改善了1,3-PDO的生产。最后，在最佳发酵条件下，大肠杆菌JA11的产量为13.47 g / L 1,3-PDO，产量为0.64 mol / mol，与原始工程大肠杆菌JA03相比分别提高了325％和100％。。