UNS: Microbial detoxification of cellulosic biomass hydrolysates by anaerobic removal and recovery of aromatic compounds

UNS：通过厌氧去除和回收芳香族化合物对纤维素生物质水解产物进行微生物解毒

• 批准号: 1506820
• 负责人: Daniel Noguera
• 金额: $ 29.95万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1506820&HistoricalAwards=false
• 关键词: UNS; Microbial; detoxification; cellulosic; biomass

PI: Daniel R. NogueraProposal Number: 1506820A major challenge facing the production of biofuels from plant biomass is the presence of unwanted byproducts resulting from the conversion of the cellulosic portions of the biomass to fermentable sugars. These byproducts, primarily from the water soluble lignin fraction of the biomass, are toxic to the fermentation process, and reduce biofuel production yield. This project will investigate the use of bacteria to convert these byproducts into a single aromatic compound which can be recovered as a valued co-product in an engineered biological process without consuming the valuable sugars. The course of this research will also advance fundamental understanding on how related anaerobic microbial processes affect the natural carbon cycle. Other impacts of the project include educational activities related to mentoring high school, undergraduate, and graduate students on topics related to the research.The overall goal of this proposed research is to study the potential of anaerobic bacteria to convert plant-derived aromatic compounds found in cellulosic biomass hydrolysates into a single phenolic compound that can be recovered as a valued co-product in a cellulosic biorefinery. The proposed approach takes advantage of anaerobic microbial degradation of aromatic compounds, and in particular, the metabolism of cultured members of the Rhodopseudomonas genus that are effective at consuming a large variety of aromatic compounds without utilizing the sugars needed for biofuel production. It is hypothesized that the aromatics present in the hydrolysates are degraded R. palustris through the benzoyl-CoA pathway. The proposed research will genetically engineer this organism to transform the large diversity of aromatics typically present in biomass hydrolysates to either benzoic acid or p-hydroxybenzoic acid, depending on the location of the mutation. The metabolic diversity of an existing Rhodopseudomonas collection will be tested to identify the best strains for detoxification of cellulosic hydrolysates. Experiments will be carried out with a mixture of the Rhodopseudomonas strains under phototrophic and denitrifying conditions, using both corn stover hydrolysates prepared with industrially relevant biomass loadings as well as variations of a synthetic medium that simulates the hydrolysate. The genetic and regulatory networks of anaerobic aromatic degradation in the best performing Rhodopseudomonas strains will be reconstructed, using RNA-Seq and genome re-sequencing. Once the strain has been engineered to promote the biotransformation of aromatics as benzoic acid, the rate processes for removal of aromatic compounds from cellulosic hydrolysates and the recovery of the benzoic acid co-product will be studied in bioreactor systems. Research outcomes will be used to enhance content for three courses in the Environmental Engineering program at the University of Wisconsin, Madison.

PI：Daniel R. Nogueraproproposal编号：1506820a由植物生物量生产生物燃料面临的主要挑战是由于生物量的纤维素部分转化为可发酵糖而导致的不需要的副产品。 这些副产品主要来自生物质的水溶性木质素部分，对发酵过程有毒，并降低生物燃料的产量。 该项目将调查细菌将这些副产物转化为单个芳香化合物的使用，该化合物可以在工程生物学过程中作为有价值的副产品回收，而无需食用有价值的糖。 这项研究的过程还将促进对相关厌氧微生物过程如何影响自然碳循环的基本理解。该项目的其他影响包括与指导高中，本科和研究生有关研究有关的教育活动。这项拟议的研究的总体目标是研究厌氧菌细菌在植物衍生的芳族化合物中的潜力，将在纤维素生物群水解物中转化为纤维素生物盐​​水解物中的该研究的潜在，可以将单个姿势化合物转化为单个酚类化合物，可以将其恢复为colle colore acter acter auite aut aupe aute aute aute aute aute aute aute aute aute auped aup auped aup propodopodopopodopodopopodauce colle coll 所提出的方法利用了芳香族化合物的厌氧微生物降解，尤其是Rhodopseudomonas属的培养成员的代谢，这些成员有效地消耗了多种芳族化合物，而无需使用生物燃料生产所需的糖。 假设存在于水解物中的芳香剂通过苯甲酰辅酶A途径降解。 拟议的研究将基因研究这种生物，以转化生物质水解物中通常存在于苯甲酸或p-羟基苯甲酸的大量芳香剂，具体取决于突变的位置。 将测试现有的Rhodopseudomonas收集的代谢多样性，以鉴定纤维素水解物排毒的最佳菌株。 实验将在光养分和非硝化条件下使用杜鹃花菌株的混合物进行，使用两种用工业相关的生物质载荷制备的玉米秸秆水解物以及模拟水解物的合成培养基的变化。 在最佳性能的杜鹃花菌株中，厌氧芳香族降解的遗传和调节网络将使用RNA-SEQ和基因组重新序列重建。 一旦菌株被设计为促进芳香族剂的生物转化为苯甲酸，将在生物反应器系统中研究从纤维素水解物中去除芳族化合物的速率过程，并将研究苯甲酸氧化剂的回收。 研究成果将用于增强威斯康星大学麦迪逊大学环境工程计划的三个课程的内容。