Molecular Characterization of Acyl-CoA Dehydrogenases

描述（申请人摘要）：酰基辅酶A脱氢酶（ACD）是一种 进化上相关的酶家族，参与了蛋白质合成的第一步。 脂肪酸的B-氧化和亮氨酸的中间代谢， 异亮氨酸和缬氨酸。这些酶的缺乏是导致 人类遗传的新陈代谢缺陷。长期目标是 项目一直在研究重要的结构/功能关系， ACD基因家族我们的一般假设是，这些信息将 更好地了解患者的基因型/表型相关性 缺乏这些酶。在过去的融资周期中，我们 在表征结构、酶性质和 异戊酰辅酶A脱氢酶（IVD）的生物起源，以及鉴定 异戊酸血症患者中的大量IVD突变。具体目标 该更新应用包括目标1：WD催化剂的表征 目的2：确定重要的氨基酸残基和基序， 目标3：阐明IVD同四聚体的作用机制 ACDs与电子传递黄素蛋白的相互作用， 这些酶的电子受体定点诱变 结构分析和分子建模将用于创建突变体 酶和新的生物物理技术将被开发，这将有助于 研究这些特性。这项工作将导致更全面的了解 ACD基因家族，并最终提高诊断和 治疗缺乏这些酶的患者。

DESCRIPTION (applicant's abstract): The acyl-CoA dehydrogenases (ACDs) are a family of evolutionarily related enzymes involved in the first step of the B-oxidation of fatty acids and in the intermediate metabolism of leucine, isoleucine and valine. Deficiencies of these enzymes are important causes of inherited defects of metabolism in humans. The long-range objective of this project has been to investigate important structure/function relationships in the ACD gene family. Our general hypothesis is that this information will afford a better understanding of genotype/phenotype correlations in patients with deficiencies of these enzymes. In previous funding periods, we have made significant strides in characterizing the structure, enzymatic properties, and biogenesis of isovaleryl-CoA dehydrogenase (IVD), as well as identifying numerous IVD mutations in patients with isovaleric acidemia. Specific aims for this renewal application include Aim 1: characterization of WD catalytic function; Aim 2: determination of amino acid residues and motifs important for stabilization of IVD homotetrainers; and Aim 3: elucidation of the mechanism of interaction of ACDs with electron transferring flavoprotein, the physiologic electron acceptor for these enzyme. Site specific mutagenesis directed by structural analysis and molecular modeling will be used to create mutant enzymes, and new biophysical techniques will be developed which will facilitate study of these properties. This work will lead to a more complete understanding of the ACD gene family, and ultimately, to an improved ability to diagnose and treat patients with deficiencies of these enzymes.