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的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。所列机构为 中心，不一定是研究者的机构。 植物形态从水生到陆生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、木脂素和单萜是最丰富的。 它们一起在植物防御和细胞壁强化中发挥重要作用，例如木脂素具有抗微生物、抗真菌、抗病毒和抗氧化特性，而木质素具有支持维管器官完整性的结构作用。一些木酚素和单萜衍生物在癌症治疗中具有广泛的应用，例如，鬼臼毒素衍生物、替尼泊苷、依托泊苷、依托泊苷和紫杉醇，它们用于治疗老年睾丸癌和小细胞肺癌，以及用于某些形式的白血病。其他的，如肠二醇/肠内酯，被认为具有预防癌症的特性，并通过膳食摄入木脂素（和可能的木质素）前体形成。因此，本项目的目标是通过高分辨率X射线结构分析来确定木酚素、木质素和单萜醇生物合成中这些关键蛋白质和酶的结构功能关系。 我们描述并比较了现在已知的木酚素途径酶、松杉醇-落叶松树脂醇还原酶和开环异落叶松树脂醇脱氢酶以及各种单木酚途径酶（例如，肉桂醇脱氢酶、芳基丙烯醛双键还原酶、肉桂酰CoA还原酶等）这些研究为探索苯丙素类化合物生物合成的调控机制、生态植物保护以及工业规模的苯丙素类化合物的区域特异性和立体特异性合成提供了重要信息。

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.