Molecular Structure and Development of Plant Cuticle Polyesters

9406354斯塔克高等植物的角质层主要起着保护叶子和果实的作用，控制细菌和真菌的侵袭以及水和化学物质的扩散。 它的主要化学成分是提供防水的蜡和两种不溶性结构聚合物，角质和木栓质。 我们的目标是了解角质和木栓质的单体单元是如何连接在一起的，聚合物是如何嵌入蜡或细胞壁基质，以及它们的超分子结构是如何与表皮功能相关的。提出了几个新的光谱和生物化学倡议：（1）温度胁迫对番茄角质层功能和灵活性的影响将通过测量其渗透性和进行固态13 C核磁共振（NMR）实验来监测;（2）分别通过对角质和水的13 C和2 H NMR测量来评估溶胀对角质网的影响;（3）水果角质和马铃薯木栓质的寡聚片段将被酶促产生并使用高效液相色谱、质谱和溶液状态NMR鉴定;（4）利用均匀和选择性的13 C和2 H标记来检查创伤愈合马铃薯组织中木栓质的发育和分子结构，结合先进的13 C和双共振NMR实验。 我们的总体目标是了解使水果外表皮具有弹性和抵抗病原体攻击的化学结构，特别是在环境压力条件下。 通过研究在受伤植物组织表面形成的木栓素的生物合成和结构发育，我们也希望设计出增强这种保护过程的方法。 由于这两种表皮膜都涉及聚合物混合物，因此我们的研究可能在合成涂料（防水）和复合材料（粘合剂）的设计中具有未来的应用。 ***

9406354 Stark The cuticle of higher plants functions primarily as a protective barrier for the leaves and fruit, controlling bacterial and fungal attack as well as the diffusion of water and chemicals. Its major chemical constituents are waxes that provide waterproofing and either of two insoluble structural polymers, cutin and suberin. Our objectives are to understand how the monomer units of cutin and suberin are linked together, how the polymers are embedded within wax or cell-wall matrices, and how their supramolecular architecture is related to cuticular function. Several new spectroscopic and biochemical initiatives are proposed: (1) the effects of temperature stress on tomato cuticle function and flexibility will be monitored by measuring its permeability and conducting solid-state 13C nuclear magnetic resonance (NMR) experiments; (2) the effects of swelling on the cuticular netting will be assessed with 13C and 2H NMR measurements on the cutin and water, respectively; (3) oligomeric fragments of fruit cutin and potato suberin will be produced enzymatically and identified using high-performance liquid chromatography, mass spectrometry, and solution-state NMR; (4) the development and molecular structure of suberin within wound-healing potato tissue will be examined using both uniform and selective 13C and 2H labelling, in conjunction with advanced 13C and double-resonance NMR experiments. %%% Our overall goal is to understand the chemical structures that make the outer cuticular skin of fruits resilient and resistant to pathogenic attack, especially under conditions of environmental stress. By studying the biosynthesis and structural development of suberin that forms on the surface of wounded plant tissue, we also hope to design methods to enhance this protective process. Since polymeric mixtures are involved in both of these cuticular membranes, our research may have future applications in the design of synthetic coating (waterproofing) and composites (adhesives). ***