SBIR Phase I: Development of an Engineered Yeast Strain for the Production of Butanol - a Second Generation Biofuel

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。这个小企业创新研究第一阶段项目描述了一种含有丁醇生物合成途径的新型重组酿酒酵母菌株的工程设计。目前，大多数丁醇技术的发展集中在对Clostridium属的丙酮-丁醇-乙醇（ABE）发酵微生物的遗传操作上。虽然有几种梭状芽孢杆菌具有通过ABE途径产生丁醇的天然能力，但丁醇的产量很低，因此这些菌株很难在商业上可行。为了避免这一限制，利用基因工程技术将乙酰丁酸梭菌合成丁醇的相关基因导入酵母。选择这种简单的真核生物是因为它在工业发酵中的健壮性，也因为它是一种遗传上易于处理的生物。结合我们的工作，使酵母能够消化和利用纤维素作为原料，我们期望产生一种能够将生物质转化为下一代生物燃料和工业溶剂的微生物。大量的研究和开发已经投入到从生物质中生产乙醇；虽然乙醇生产是最成熟的生物燃料技术，但其他以酒精为基础的燃料，如丁醇，也可用作汽油的可再生替代品。与乙醇相比，丁醇具有许多优点，包括更高的能量含量；丁醇可以直接用作现有车辆的燃料，无需改装；丁醇的腐蚀性比乙醇小，可以通过现有的管道基础设施输送。从石油中生产的丁醇目前被用作工业溶剂或制造塑料的原料，在全球拥有数十亿美元的现有市场。当前的经济气候迫使人们确定新的制造工艺，以取代石油的使用。因此，人们对利用可再生资源发酵丁醇越来越感兴趣。在整个20世纪40年代，丁醇是由梭状芽孢杆菌属的细菌发酵产生的。出于经济考虑，以石油为原料的生产工艺取代了商业规模的发酵。通过利用非食品原料，Arbor Fuel公司将构建的酵母菌株可以在减少我国对石油的依赖和提高可再生能源的利用率方面发挥重要作用。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This Small Business Innovation Research Phase I project describes the engineering of a novel recombinant Saccharomyces cerevisiae strain containing the butanol biosynthetic pathway. Currently, most butanol technology development focuses on the genetic manipulation of the Acetone-Butanol-Ethanol (ABE) fermentation microorganisms of the genus Clostridium. While several Clostridium species have the natural ability to make butanol via the ABE pathway, the amount of butanol produced is low, and therefore these strains would struggle to be commercially viable. To avoid this limitation, the genes involved in the butanol biosynthesis from Clostridium acetobutylicum were introduced into the yeast Sacharomyces cerevisiae using genetic engineering techniques. This simple eukaryote was chosen because of its robust nature in industrial fermentation and also because it is a genetically tractable organism. When combined with our work enabling yeast to digest and utilize cellulose as a feedstock, we expect to have generated a microbe capable of converting biomass into a next generation biofuel and industrial solvent.Much research and development has gone into the production of ethanol from biomass; although ethanol production is the most mature biofuel technology, other alcohol-based fuels, such as butanol, can be used as renewable replacements for gasoline. Butanol offers a number of benefits over ethanol including higher energy content; butanol can be used directly as a fuel in current vehicles without modification; butanol is less corrosive than ethanol and can be piped through the existing pipeline infrastructure. Butanol produced from petroleum is currently used as an industrial solvent or as feedstock for manufacturing plastics and has an existing market of several billion dollars worldwide. The current economic climate has forced the identification of new manufacturing processes that replace the use of petroleum. As a result, there is growing interest in fermentation of butanol from renewable resources. Through the 1940s, butanol was produced as a fermentation product by bacteria from the genus Clostridium. Due to economic considerations, manufacturing processes utilizing petroleum as the raw material replaced commercial scale fermentation. By utilizing non-food feedstock, the yeast strain that Arbor Fuel Inc will construct could play a significant role in reducing our country's reliance on petroleum and increase the utilization of renewable energy resources.