The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby, Denmark.
Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK.
Microb Biotechnol. 2024 Apr;17(4):e14460. doi: 10.1111/1751-7915.14460.
Aromatic compounds are used in pharmaceutical, food, textile and other industries. Increased demand has sparked interest in exploring biotechnological approaches for their sustainable production as an alternative to chemical synthesis from petrochemicals or plant extraction. These aromatic products may be toxic to microorganisms, which complicates their production in cell factories. In this study, we analysed the toxicity of multiple aromatic compounds in common production hosts. Next, we screened a subset of toxic aromatics, namely 2-phenylethanol, 4-tyrosol, benzyl alcohol, berberine and vanillin, against transporter deletion libraries in Escherichia coli and Saccharomyces cerevisiae. We identified multiple transporter deletions that modulate the tolerance of the cells towards these compounds. Lastly, we engineered transporters responsible for 2-phenylethanol tolerance in yeast and showed improved 2-phenylethanol bioconversion from L-phenylalanine, with deletions of YIA6, PTR2 or MCH4 genes improving titre by 8-12% and specific yield by 38-57%. Our findings provide insights into transporters as targets for improving the production of aromatic compounds in microbial cell factories.
芳香族化合物在制药、食品、纺织和其他行业中有广泛应用。由于需求增加，人们对探索生物技术方法来可持续生产这些化合物产生了兴趣，以替代从石化产品或植物提取的化学合成方法。这些芳香族产品可能对微生物有毒性，这使得它们在细胞工厂中的生产变得复杂。在这项研究中，我们分析了多种常见生产宿主中芳香族化合物的毒性。接下来，我们筛选了一组有毒芳香族化合物，即 2-苯乙醇、4-羟基苯乙醇、苯甲醇、小檗碱和香草醛，针对大肠杆菌和酿酒酵母的转运蛋白缺失文库进行了筛选。我们鉴定了多个转运蛋白缺失突变，这些突变可调节细胞对这些化合物的耐受性。最后，我们对负责酵母中 2-苯乙醇耐受性的转运蛋白进行了工程改造，并展示了从 L-苯丙氨酸生物转化 2-苯乙醇的改进，YIA6、PTR2 或 MCH4 基因的缺失使产量提高了 8-12%，比产率提高了 38-57%。我们的研究结果为利用转运蛋白作为目标来改善微生物细胞工厂中芳香族化合物的生产提供了新的见解。
