程酵母来加强生物燃料生产的一个方法。通过代谢工程，酶能够将比以前更多的纤维素生物质（从木材、草本和不可食用的植物材料生成）转化成乙醇。
不可食用的纤维素生物质向生物燃料的微生物转化目前有若干局限性。生物质大部分是木糖，微生物要代谢的是它们；而其他成分在代谢过程中会导致乙酸的形成。这对微生物是有毒的，因此会进一步降低转化率。Yong-Su Jin及同事证明，他们的工程酵母对木糖和乙酸都能代谢，从而能够利用更多的生
The anticipation for substituting conventional fossil fuels with cellulosic biofuels is growing in the face of increasing demand for energy and rising concerns of greenhouse gas emissions. However， commercial production of cellulosic biofuel has been hampered by inefficient fermentation of xylose and the toxicity of acetic acid， which constitute substantial portions of cellulosic biomass. Here we use a redox balancing strategy to enable efficient xylose fermentation and simultaneous in situ detoxification of cellulosic feedstocks. By combining a nicotinamide adenine dinucleotide (NADH)-consuming acetate consumption pathway and an NADH-producing xylose utilization pathway， engineered yeast converts cellulosic sugars and toxic levels of acetate together into ethanol under anaerobic conditions. The results demonstrate a breakthrough in making efficient use of carbon compounds in cellulosic biomass and present an innovative strategy for metabolic engineering whereby an undesirable redox state can be exploited to drive desirable metabolic reactions， even improving productivity and yield.
物质以及提高转化率和产量
