Huang Xing-Feng, Reardon Kenneth F
Department of Chemical and Biological Engineering, Colorado State University, Fort Collins, CO 80523-1370, USA.
FEMS Yeast Res. 2021 Dec 15;21(8). doi: 10.1093/femsyr/foab056.
One strategy to increase the yield of desired fermentation products is to redirect substrate carbon from biomass synthesis. Nongenetic approaches to alter metabolism may have advantages of general applicability and simple control. The goal of this study was to identify and evaluate chemicals for their ability to inhibit the growth of Saccharomyces cerevisiae while allowing ethanol production with higher yields. Eight potential growth-inhibitory chemicals were screened for their ability to reduce cell growth in 24-well plates. Effective chemicals were then evaluated in cultivations to identify those that simultaneously reduced biomass yield and increased ethanol yield. The yeast quorum-sensing molecules 2-phenylethanol, tryptophol and tyrosol were found to increase the ethanol yield of S. cerevisiae JAY 270. These molecules were tested with seven other yeast strains and ethanol yields of up to 15% higher were observed. The effects of 2-phenylethanol and tryptophol were also studied in bioreactor fermentations. These findings demonstrate for the first time that the ethanol yield can be improved by adding yeast quorum-sensing molecules to reduce the cell growth of S. cerevisiae, suggesting a strategy to improve the yield of ethanol and other yeast fermentation products by manipulating native biological control systems.
提高所需发酵产物产量的一种策略是将底物碳从生物质合成中转移出来。改变代谢的非基因方法可能具有普遍适用性和易于控制的优点。本研究的目的是识别和评估能够抑制酿酒酵母生长同时使乙醇产量更高的化学物质。筛选了八种潜在的生长抑制化学物质在24孔板中降低细胞生长的能力。然后在培养中评估有效的化学物质，以确定那些同时降低生物质产量并提高乙醇产量的物质。发现酵母群体感应分子2-苯乙醇、色醇和酪醇可提高酿酒酵母JAY 270的乙醇产量。用其他七种酵母菌株对这些分子进行了测试，观察到乙醇产量提高了15%。还在生物反应器发酵中研究了2-苯乙醇和色醇的作用。这些发现首次证明，通过添加酵母群体感应分子来降低酿酒酵母的细胞生长，可以提高乙醇产量，这为通过操纵天然生物控制系统提高乙醇和其他酵母发酵产物的产量提供了一种策略。
