STRUCTURE BASED KINETICS IN POLYSACCHARIDES BY TIME RESOLVED X-RAY CRYSTALLOG

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 多糖是生物体中普遍存在的一类独特的生物聚合物。它们具有广泛的不同化学结构，并表现出各种独特的分子和堆积结构。广泛的来源与固有的功能行为相结合，赋予了它们在食品配方中的广泛应用。此外，其独特的性质，如可再生性、生物降解性和生物活性，催生了在制药和医药用途方面的新应用的发展。许多多糖是水溶性的，构成了人类消费的大部分食物。在食品配方中，它们被用来控制功能性质，如水分结合、粘度、增稠和分散体的稳定性。有趣的是，添加食品配料会显着改变其物理性质，即溶解性、吸湿性和结晶度。例如，糖的加入改变了溶剂的性质，而盐促进了水胶体之间的凝胶化。在这方面，对多糖与盐、糖和水等食品成分之间的物理和化学相互作用以及在这些相互作用过程中发生的结构转变的详细了解，有助于揭示导致食品系统宏观行为的潜在分子机制。对几种蛋白质结构的时间分辨结晶学研究揭示了关于它们的化学动力学的丰富信息。我们希望利用类似的方法通过一系列随时间变化的结晶学数据分析来揭示多糖基质中的动力学机制。 目前的建议是关于确定一些具有重要生物学意义和工业用途的多糖在与溶剂、溶质和小分子相互作用过程中的结构变化。本研究包括三种藻类多糖，即卡拉胶、卡拉胶和卡拉胶。我们坚信，这项研究的结果将有助于破译多糖的分子机制，从而开发出具有所需功能性的新型功能食品。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Polysaccharides comprise a distinct class of biopolymers produced universally among the living organisms. They have extensive group of different chemical structures and exhibit a variety of unique molecular and packing structures. The wide range of sources combined with the intrinsic functional behavior bestows their widespread utilization in food formulations. Further their unique properties such as renewability biodegradability and biological activity spawn the development of novel applications in pharmaceutical and medicinal uses. Many of the polysaccharides are water soluble and form the bulk of foods consumed by humans. In food formulations they are used to control the functional properties such as water binding viscosity thickening and stability of dispersions. Interestingly addition of food ingredients significantly alters their physical properties namely the solubility hydroscopicity and crystallinity. For example incorporation of sugar modifies the solvent properties whereas salt promotes gelation among the hydrocolloids. In this regard a detailed knowledge about the physical and chemical interactions among the polysaccharides and food ingredients such as salt sugar and water as well as the structural transitions that takes place during such interactions enlightens the underlying molecular mechanisms that are responsible for the macroscopic behavior of the food systems. Time resolved crystallographic studies on several protein structures have revealed a wealth of information about their chemical kinetics. We would like to utilize similar approach to unravel the kinetic mechanism in the polysaccharide matrices through a series of time-dependent crystallographic data analysis. The current proposal is about determining the architectural changes in a number of biologically important and industrially useful polysaccharides during their interactions with solvent solute and small molecules. The study includes three algal polysaccharides namely iota-carrageenan kappa-carrageenan and lambda carrageenan. We strongly believe that the outcome of this study will shed light towards deciphering the molecular mechanisms of polysaccharides leading to the development of novel functional foods with desired functionality.