Chen Binbin, Lee Dong-Yup, Chang Matthew Wook
Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, Singapore 117599, Singapore; NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), Life Sciences Institute, National University of Singapore, 28 Medical Drive, Singapore 117456, Singapore.
NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), Life Sciences Institute, National University of Singapore, 28 Medical Drive, Singapore 117456, Singapore; Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore.
Metab Eng. 2015 Sep;31:53-61. doi: 10.1016/j.ymben.2015.06.009. Epub 2015 Jul 8.
Biological production of terminal alkenes has garnered a significant interest due to their industrial applications such as lubricants, detergents and fuels. Here, we engineered the yeast Saccharomyces cerevisiae to produce terminal alkenes via a one-step fatty acid decarboxylation pathway and improved the alkene production using combinatorial engineering strategies. In brief, we first characterized eight fatty acid decarboxylases to enable and enhance alkene production. We then increased the production titer 7-fold by improving the availability of the precursor fatty acids. We additionally increased the titer about 5-fold through genetic cofactor engineering and gene expression tuning in rich medium. Lastly, we further improved the titer 1.8-fold to 3.7 mg/L by optimizing the culturing conditions in bioreactors. This study represents the first report of terminal alkene biosynthesis in S. cerevisiae, and the abovementioned combinatorial engineering approaches collectively increased the titer 67.4-fold. We envision that these approaches could provide insights into devising engineering strategies to improve the production of fatty acid-derived biochemicals in S. cerevisiae.
由于末端烯烃在润滑剂、洗涤剂和燃料等工业应用中的用途，其生物生产已引起了广泛关注。在此，我们对酿酒酵母进行了工程改造，使其通过一步脂肪酸脱羧途径生产末端烯烃，并采用组合工程策略提高了烯烃产量。简而言之，我们首先对8种脂肪酸脱羧酶进行了表征，以实现并提高烯烃产量。然后，我们通过提高前体脂肪酸的可用性，将产量提高了7倍。此外，我们通过在丰富培养基中进行基因辅因子工程和基因表达调控，使产量又提高了约5倍。最后，我们通过优化生物反应器中的培养条件，将产量进一步提高了1.8倍，达到3.7 mg/L。本研究是酿酒酵母中末端烯烃生物合成的首次报道，上述组合工程方法共同使产量提高了67.4倍。我们设想，这些方法可为设计工程策略以提高酿酒酵母中脂肪酸衍生生化物质的产量提供思路。
