Identification and characterization of components involved in mannan synthesis to increase lignocellulosic biofuel production

甘露聚糖合成中涉及的成分的鉴定和表征，以提高木质纤维素生物燃料的产量

• 批准号: 286181067
• 负责人: Dr. Thea Pick
• 金额: --
• 依托单位: Joint BioEnergy Institute
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/286181067?language=en
• 关键词: Identification; characterization; components; involved; mannan

Plant biomass serves as an abundant renewable source for biofuel and bioenergy production. In bioenergy production processes, plant-derived sugars such as starch, sucrose, cellulose, and hemicellulose are used for fermentation by microorganisms (yeast, bacteria) to produce desired products. Primarily food crops, like Zea mays (corn) and Saccharum officinarum (sugarcane) are currently used for the production of first-generation biofuels. As energy demand steadily increases the competing priorities between energy production needs and food supply will grow significantly. In response, the US and European governments have mandated that a sustainable amount of renewable fuel be derived from non-food crops (second-generation biofuels) in five to seven years. Achieving this mandate requires extensive basic research and scientific advancements to optimize and boost the fermentation process of non-food plant tissues, namely lignocellulosic feedstocks. A promising approach to facilitate fermentation of lignocellulosic feedstocks is to increase the C6 sugar content, e.g. mannans, in plant cell walls. Plant cell walls are mainly composed of cellulose, hemicellulose, and lignin. Only cellulose and hemicellulose contain C6 sugars. In cellulose these sugars are packed in crystalline arrays and are least accessible to microbial fermentation. The C6 sugars in hemicellulose, like mannans, are better accessible to microbial enzymes and are therefore a suitable target for plant cell wall engineering. As a DFG fellow, I propose to identify and characterize components involved in mannan synthesis to increase the glucomannan content in plant cell walls. This work will generate basic knowledge of mannan biosynthesis that will help to boost biofuel production through improved fermentation. To reach this goal I will (1) use an in silico analysis to filter and analyze coexpression databases to identify genes co-expressed with known components involved in mannan biosynthesis and will use existing data sets to generate a new set of candidate genes. (2) analyze the top candidates on a molecular and biochemical level to detect the candidates role in mannan biosynthesis and in global plant metabolism. (Arabidopsis thaliana will be used as a model plant.) (3) use a bioinformatics approach and computational modeling to predict which combination of components and which expression and regulation of components will lead to an increased mannan content in plant cell walls. I hypothesize that these results will lead to a near complete picture of mannan biosynthesis. The ultimate goal of this work is to create a plant with increased mannan content in plant cell walls to boost biofuel production through improved fermentation.

植物生物质是生物燃料和生物能源生产的丰富可再生资源。在生物能源生产过程中，淀粉、蔗糖、纤维素和半纤维素等植物来源的糖被微生物(酵母、细菌)发酵以产生所需的产品。玉米(玉米)和甘蔗(甘蔗)等粮食作物目前主要用于生产第一代生物燃料。随着能源需求的稳步增长，能源生产需求和粮食供应之间的竞争优先事项将显着增加。作为回应，美国和欧洲政府已要求在5至7年内从非粮食作物(第二代生物燃料)中提取可持续数量的可再生燃料。实现这一任务需要广泛的基础研究和科学进步，以优化和促进非食用植物组织的发酵过程，即木质纤维原料。提高植物细胞壁中C6糖的含量，例如甘露聚糖，是促进木质纤维原料发酵的一种有前途的方法。植物细胞壁主要由纤维素、半纤维素和木质素组成。只有纤维素和半纤维素含有C6糖。在纤维素中，这些糖被包装成晶状排列，最不容易被微生物发酵。与甘露聚糖一样，半纤维素中的C6糖更容易被微生物酶所利用，因此是植物细胞壁工程的合适靶标。作为DFG成员，我建议鉴定和表征参与甘露聚糖合成的成分，以增加植物细胞壁中葡甘露聚糖的含量。这项工作将产生甘露聚糖生物合成的基本知识，这将有助于通过改进发酵来提高生物燃料的产量。为了实现这一目标，我将(1)使用电子分析来筛选和分析共表达数据库，以确定与参与甘露聚糖生物合成的已知组分共表达的基因，并将使用现有的数据集来生成新的候选基因集。(2)从分子水平和生化水平对候选基因进行分析，以确定候选基因在甘露聚糖生物合成和全球植物代谢中的作用。(3)利用生物信息学的方法和计算模型来预测植物细胞壁中甘露糖的含量将会增加哪些成分的组合以及哪些成分的表达和调控。我推测，这些结果将导致甘露聚糖生物合成的近乎完整的图景。这项工作的最终目标是创造一种植物，使植物细胞壁中的甘露聚糖含量增加，通过改进发酵来提高生物燃料的产量。