Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 136-702, Republic of Korea.
Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 136-702, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 151-921, Republic of Korea.
Bioresour Technol. 2015 Sep;191:445-51. doi: 10.1016/j.biortech.2015.03.057. Epub 2015 Mar 17.
The aim of this work was to apply the evolutionary engineering to construct a mutant Saccharomyces cerevisiae HJ7-14 resistant on 2-deoxy-D-glucose and with an enhanced ability of bioethanol production from galactose, a mono-sugar in red algae. In batch and repeated-batch fermentations, HJ7-14 metabolized 5-fold more galactose and produced ethanol 2.1-fold faster than the parental D452-2 strain. Transcriptional analysis of genes involved in the galactose metabolism revealed that moderate relief from the glucose-mediated repression of the transcription of the GAL genes might enable HJ7-14 to metabolize galactose rapidly. HJ7-14 produced 7.4 g/L ethanol from hydrolysates of the red alga Gelidium amansii within 12 h, which was 1.5-times faster than that observed with D452-2. We demonstrate conclusively that evolutionary engineering is a promising tool to manipulate the complex galactose metabolism in S. cerevisiae to produce bioethanol from red alga.
本工作旨在应用进化工程构建一株耐 2-脱氧-D-葡萄糖的突变酿酒酵母 HJ7-14，提高其利用红藻中单糖半乳糖生产生物乙醇的能力。在分批和重复分批发酵中，HJ7-14 代谢半乳糖的速度比亲本 D452-2 菌株快 5 倍，生产乙醇的速度快 2.1 倍。参与半乳糖代谢的基因的转录分析表明，适度缓解葡萄糖对半乳糖基因转录的抑制作用可能使 HJ7-14 能够快速代谢半乳糖。HJ7-14 在 12 小时内从红藻江蓠的水解产物中生产了 7.4 g/L 的乙醇，比 D452-2 观察到的速度快 1.5 倍。我们明确证明，进化工程是一种有前途的工具，可以操纵酿酒酵母中复杂的半乳糖代谢，从而从红藻生产生物乙醇。
