Engineered Saccharomyces cerevisiae capable of simultaneous cellobiose and xylose fermentation
메타 데이터
바이오화학분류
바이오플라스틱
플라스틱
바이오정밀화학
용매
화학제품
연료
화장품용 기능성소재
계면활성제⁄증점제
의료용 화학소재
식품첨가제
논문
Engineered Saccharomyces cerevisiae capable of simultaneous cellobiose and xylose fermentation
학술지
Proceedings of the National Academy of Sciences of the United States of America
저자명
Ha, Suk-Jin; Galazka, Jonathan M.; Rin Kim, Soo; Choi, Jin-Ho; Yang, Xiaomin; Seo, Jin-Ho; Louise Glass, N.; Cate, Jamie H. D.; Jin, Yong-Su
초록
<P> The use of plant biomass for biofuel production will require efficient utilization of the sugars in lignocellulose, primarily glucose and xylose. However, strains of <I>Saccharomyces cerevisiae</I> presently used in bioethanol production ferment glucose but not xylose. Yeasts engineered to ferment xylose do so slowly, and cannot utilize xylose until glucose is completely consumed. To overcome these bottlenecks, we engineered yeasts to coferment mixtures of xylose and cellobiose. In these yeast strains, hydrolysis of cellobiose takes place inside yeast cells through the action of an intracellular β-glucosidase following import by a high-affinity cellodextrin transporter. Intracellular hydrolysis of cellobiose minimizes glucose repression of xylose fermentation allowing coconsumption of cellobiose and xylose. The resulting yeast strains, cofermented cellobiose and xylose simultaneously and exhibited improved ethanol yield when compared to fermentation with either cellobiose or xylose as sole carbon sources. We also observed improved yields and productivities from cofermentation experiments performed with simulated cellulosic hydrolyzates, suggesting this is a promising cofermentation strategy for cellulosic biofuel production. The successful integration of cellobiose and xylose fermentation pathways in yeast is a critical step towards enabling economic biofuel production. </P>