A THALIANA DOUBLE BOND REDUCTASE APO-FORM, BINARY AND TERNARY COMPLEXES

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 植物形态从水生植物向陆生植物的演变伴随着维管植物中大量酚类成分的形成，其中木质素、木脂素和单萜含量最丰富。它们共同在植物防御和细胞壁加固中发挥重要作用，如木脂素具有抗菌、抗真菌、抗病毒和抗氧化特性，而木质素具有支持维管束完整性的结构作用。一些木脂素和单萜衍生物在癌症治疗中得到了广泛的应用，例如鬼臼毒素衍生物、替尼平苷、依托泊苷、依托泊酚和紫杉醇，用于治疗生发睾丸癌和小细胞肺癌，以及某些形式的白血病。其他化合物，如肠二醇/肠内酯，被认为具有防癌特性，是通过饮食摄入木脂素(可能还有木质素)前体而形成的。因此，本项目的目标是通过高分辨率X射线结构分析，确定木质素、木质素和单醇醇生物合成中这些关键蛋白质和酶的结构和功能关系。我们描述和比较了目前已知的木脂素途径酶、松脂醇-落叶松脂醇还原酶和二异落叶松脂醇脱氢酶以及各种单醇途径酶(如肉桂醇脱氢酶、芳基丙酸双键还原酶、肉桂酰辅酶A还原酶等)的作用机理(区域专一性和对映专一性)。从这些研究中获得的信息将非常有助于探索生态植物保护中苯丙烷生物合成的规律，以及这些药理活性物质的区域特异性和立体特异性的工业化合成。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The evolution of plant forms from an aquatic to a land base was accompanied by formation of a vast plethora of phenolic components in the vascular plants, of which the lignins, lignans and monoterpene are the most abundant. Together they play important roles in plant defense and cell wall reinforcement, such as with the lignans having antimicrobial, antifungal, antiviral and antioxidant properties, whereas the lignins have structural roles in support of vascular apparatus integrity. Some lignans and monoterpene derivatives find widespread application in cancer treatment, e.g., the podophyllotoxin derivatives, teniposide, etoposide, etopohos and taxol which are used in treatment of germinal testicular and small cell lung cancers, and for certain forms of leukemia. Others,such as enterodiol/enterolactone, are believed to have cancer-preventing properties and are formed through dietary ingestion of lignans (and possibly lignin) precursors. The goal of this project is thus to define the structure function relationships of these key proteins and enzymes in lignan, lignin and monolignol biosynthesis through high resolution X-ray structural analyses. We describe and compare what is now known about the mechanistic (regiospecificity and enantiospecificity) basis of the lignan pathway enzymes, pinoresinol-lariciresinol reductase and secoisolariciresinol dehydrogenase as well as of various monolignol pathway enzymes (e.g., cinnamyl alcohol dehydrogenase, arylpropenal double bond reductase, cinnamoyl CoA reductase, etc.) The information gained from these studies will be very useful for exploring the regulation of phenylpropanoid biosynthesis for ecological plant protection, and for the industrial-scale regiospecific and stereospecific synthesis of these pharmacologically active substances.