Regulation of starch synthesis in higher plants

高等植物淀粉合成的调控

• 批准号: 262209-2008
• 负责人: Emes, Michael
• 金额: $ 4.01万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=480185
• 关键词: Regulation; starch; synthesis; higher; plants

Starch is the primary source of calorific intake for mankind. As a commodity, it has wide application in the food and non-food sectors. As a food-stuff, particular types of starch known as resistant starch (RS) provide additional health benefits because of their effects on the rate of glucose absorption into the blood stream and through a pre-biotic function in the large colon where RS contributes to dietary fibre with positive benefits for colorectal health. Within the non-food sector it has many applications, including areas as diverse as the paper and board industry, biodegradable plastics, drug delivery, dry-wall manufacture, and as a replacement for hydrocarbon ingredients in paint. Increasingly it is being used as a feedstock in the energy industry for the production of bio-ethanol as an alternative to fossil fuels. Starch is a polymer made of glucose units joined together in linear chains with periodic branching giving rise to a highly organized, semi-crystalline, insoluble structure. It is biological variation in the fine-structure of starch which gives rise to its diversity of application and functionality. Despite its enormous significance for mankind, our fundamental knowledge of how it is made is still lacking to the point where we are not in a position to produce tailor-made starches for particular end-uses, other than through the use of significant chemical modification which often has deleterious environmental impact as a result of effluent by-products. Starch synthesis is dependent upon the cooperative activities of a large number of enzymes. The work described in this program of research will address basic questions about biochemical mechanisms which give rise to the coordinated interaction of the enzymes involved. In particular, the higher order mechanisms which facilitate biosynthesis of the starch granule will be investigated, including the formation of large multi-enzyme complexes in vivo. Understanding these mechanisms will provide increased opportunity for future biotechnological application.

淀粉是人类热量摄取的主要来源。作为一种商品，它在食品和非食品领域有着广泛的应用。作为一种食品，被称为抗性淀粉(RS)的特殊类型的淀粉提供了额外的健康益处，因为它们影响了葡萄糖进入血液的吸收速度，并通过大肠中的生物前功能，RS有助于膳食纤维，对结直肠健康有积极的好处。在非食品行业内，它有许多应用，包括纸张和纸板工业、可生物降解塑料、药物输送、干墙制造，以及作为涂料中碳氢化合物成分的替代品。它越来越多地被用作能源行业的原料，用于生产生物乙醇，作为化石燃料的替代品。淀粉是一种由葡萄糖单元连接在一起的线性链组成的聚合物，通过周期性的分支产生高度有组织的、半结晶的、不可溶的结构。正是由于淀粉的精细结构具有生物多样性，才导致其用途和功能的多样性。尽管它对人类具有巨大的意义，但我们仍然缺乏关于它是如何制成的基础知识，以至于我们无法为特定的最终用途生产量身定做的淀粉，除非通过使用重大的化学修饰，这往往会因废水副产品而对环境造成有害影响。淀粉的合成依赖于大量酶的协同作用。这项研究计划中描述的工作将解决有关生化机制的基本问题，这些机制引起所涉及的酶的协调相互作用。特别是，促进淀粉颗粒生物合成的高阶机制将被研究，包括在体内形成大的多酶复合体。了解这些机制将为未来的生物技术应用提供更多的机会。