Cabulong Rhudith B, Valdehuesa Kris Niño G, Ramos Kristine Rose M, Nisola Grace M, Lee Won-Keun, Lee Chang Ro, Chung Wook-Jin
Department of Energy Science and Technology (DEST), Energy and Environment Fusion Technology Center (E(2)FTC), Myongji University, Myongji-ro 116, Cheoin-gu, Yongin, Gyeonggi-do, 170-58, South Korea.
Division of Bioscience and Bioinformatics, Myongji University, Myongji-ro 116, Cheoin-gu, Yongin, Gyeonggi-do, 170-58, South Korea.
Enzyme Microb Technol. 2017 Feb;97:11-20. doi: 10.1016/j.enzmictec.2016.10.020. Epub 2016 Nov 1.
The microbial production of renewable ethylene glycol (EG) has been gaining attention recently due to its growing importance in chemical and polymer industries. EG has been successfully produced biosynthetically from d-xylose through several novel pathways. The first report on EG biosynthesis employed the Dahms pathway in Escherichia coli wherein 71% of the theoretical yield was achieved. This report further improved the EG yield by implementing metabolic engineering strategies. First, d-xylonic acid accumulation was reduced by employing a weak promoter which provided a tighter control over Xdh expression. Second, EG yield was further improved by expressing the YjgB, which was identified as the most suitable aldehyde reductase endogenous to E. coli. Finally, cellular growth, d-xylose consumption, and EG yield were further increased by blocking a competing reaction. The final strain (WTXB) was able to reach up to 98% of the theoretical yield (25% higher as compared to the first study), the highest reported value for EG production from d-xylose.
由于可再生乙二醇（EG）在化学和聚合物工业中的重要性日益增加，其微生物生产最近受到了关注。通过几种新途径已成功地从d-木糖生物合成EG。关于EG生物合成的第一份报告在大肠杆菌中采用了达姆斯途径，其中实现了理论产量的71%。本报告通过实施代谢工程策略进一步提高了EG产量。首先，通过使用弱启动子减少了d-木糖酸的积累，该启动子对Xdh表达提供了更严格的控制。其次，通过表达YjgB进一步提高了EG产量，YjgB被确定为大肠杆菌中最合适的内源性醛还原酶。最后，通过阻断竞争反应进一步提高了细胞生长、d-木糖消耗和EG产量。最终菌株（WTXB）能够达到理论产量的98%（比第一项研究高25%），这是从d-木糖生产EG的最高报道值。
