Genome engineering allows selective conversions of terephthalaldehyde to multiple valorized products in bacterial cells

Deconstruction of polyethylene terephthalate (PET) plastic waste generates opportunities for valorization to alternative products. We recently designed an enzymatic cascade that could produce terephthalaldehyde (TPAL) from terephthalic acid. Here, we showed that the addition of TPAL to growing cultures of Escherichia coli wild-type strain MG1655 and an engineered strain for reduced aromatic aldehyde rection (RARE) strain resulted in substantial reduction. We then investigated if we could mitigate this reduction using multiplex automatable genome engineering (MAGE) to create an E. coli strain with 10 additional knockouts in RARE. Encouragingly, we found this newly engineered strain enabled a 2.5-fold higher retention of TPAL over RARE after 24h. We applied this new strain for the production of para-xylylenediamine (pXYL) and observed a 6.8-fold increase in pXYL titer compared to RARE. Overall, our study demonstrates the potential of TPAL as a versatile intermediate in microbial biosynthe..., ,聚对苯二甲酸乙二酯（PET，polyethylene terephthalate）塑料废弃物的解聚，可为其增值转化为替代产品创造契机。我们此前设计了一套酶级联反应体系，可从对苯二甲酸合成对苯二甲醛（TPAL，terephthalaldehyde）。本研究发现，向野生型大肠杆菌（Escherichia coli）菌株MG1655以及用于减弱芳香醛还原的工程菌株（RARE）的生长培养液中添加TPAL后，TPAL会发生显著降解。随后，我们尝试通过多重自动化基因组工程（MAGE，multiplex automatable genome engineering）对RARE菌株进行改造，引入10个额外的基因敲除位点以缓解TPAL的降解。令人鼓舞的是，相较于原始RARE菌株，该新构建的工程菌株在培养24小时后可使TPAL的保留率提升2.5倍。我们将该菌株应用于对苯二甲胺（pXYL，para-xylylenediamine）的生产，结果显示其发酵滴度较RARE菌株提升了6.8倍。综上，本研究证实了TPAL作为微生物生物合成通用中间体的应用潜力……