STTR Phase I: Anaerobic fermentation system for isoprene production from lignocellulose

STTR 第一阶段：木质纤维素生产异戊二烯的厌氧发酵系统

• 批准号: 1321454
• 负责人: Phillip Brumm
• 金额: $ 22.43万
• 依托单位: C5-6 TECHNOLOGIES
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1321454&HistoricalAwards=false
• 关键词: STTR; Phase; Anaerobic; fermentation; system

This Small Business Technology Transfer (STTR) Phase I project will develop a facultative anaerobic bacterium that ferments sugars obtained from cellulosic sources into isoprene, a valuable feedstock used in the production of latex rubber, plastics, and pharmaceuticals. Isoprene also is used for the production of chemicals, or polymerized into replacements for petroleum-derived jet fuel. This work will build on prototype E. coli work by redesigning gene constructs and expressing them in the facultative anaerobic host Bacillus coagulans. Phase I of this research will entail synthesizing and cloning a set of isoprene synthase (IspS) genes into B. coagulans; this work will first evaluate ten separate potential IPS molecules to determine the best one for isoprene production in bacteria. The engineered B. coagulans strains will be evaluated for isoprene production by GC-MS headspace analysis. Achieving anaerobic isoprene production from lignocellulosic sources within at least an order of magnitude of the rates achieved in E. coli at the end of Phase I will demonstrate feasibility. Phase II will then focus on improving the flux of metabolites through the pathway to this enzyme. The broader impact/commercial potential of this project will be to develop a high efficiency bacterial strain of Bacillus coagulans to ferment sugars derived from cellulosic materials, such as pulp and pulp mill sludge into isoprene. The paper industry produces an estimated 2 million tons of fiber sludge annually. This material is either discarded in a landfill or burned, adding millions of dollars to the cost of paper production. The composition of this sludge is ~50% cellulose and hemicellulose on a dry weight basis, making it an excellent fermentation feedstock when converted into its constituent five and six carbon sugars. Isoprene is a platform chemical that is capable of playing a central role in the future bio-economy. Annual global consumption of isoprene is 1.7 billion pounds per year, of which more than 95% is used in the production of isoprene rubber, styrene-isoprene-styrene block copolymer (SIS), and butyl rubber, with an estimated price of $1.30 per pound. The balance is used in the production of high-value isoprenoid derivatives such as vitamins, nutraceuticals, pesticides, fragrances, flavors and pharmaceuticals. The project also will provide an improved understanding of the biosynthetic pathway of isoprene and other high-value isoprenoid compounds.

这个小企业技术转让（STTR）第一阶段项目将开发一种兼性厌氧细菌，将从纤维素来源获得的糖发酵成异戊二烯，异戊二烯是一种用于生产乳胶橡胶，塑料和药品的有价值的原料。异戊二烯还用于生产化学品，或聚合成石油衍生喷气燃料的替代品。 这项工作将建立在原型E。大肠杆菌通过重新设计基因构建体并在兼性厌氧宿主凝结芽孢杆菌中表达它们来工作。本研究的第一阶段将需要合成并克隆一组异戊二烯合酶（IspS）基因到B中。这项工作将首先评估十个单独的潜在IPS分子，以确定最好的一个异戊二烯生产细菌。 工程B。将通过GC-MS顶空分析评价凝结物菌株的异戊二烯产量。实现从木质纤维素源的厌氧异戊二烯生产，在至少一个数量级内实现在E.在第一阶段结束时，大肠杆菌将证明可行性。然后，第二阶段将集中于改善代谢物通过该途径到达该酶的通量。该项目更广泛的影响/商业潜力将是开发一种高效的凝结芽孢杆菌菌株，将来自纤维素材料的糖发酵成异戊二烯，如纸浆和纸浆厂污泥。 造纸工业每年产生约200万吨纤维污泥。这种材料要么被丢弃在垃圾填埋场，要么被烧毁，这给纸张生产增加了数百万美元的成本。这种污泥的成分是干重的~50%纤维素和半纤维素，使其在转化为其组成的五碳和六碳糖时成为优良的发酵原料。异戊二烯是一种平台化学品，能够在未来的生物经济中发挥核心作用。全球每年异戊二烯的消费量为17亿磅，其中95%以上用于生产异戊二烯橡胶、苯乙烯-异戊二烯-苯乙烯嵌段共聚物（SIS）和丁基橡胶，估计价格为每磅1.30美元。其余的用于生产高价值的类异戊二烯衍生物，如维生素、营养保健品、农药、香料、调味品和药品。 该项目还将提供对异戊二烯和其他高价值类异戊二烯化合物的生物合成途径的更好理解。