X RAY STRUCTURE OF UDP GALACTOPYRANOSE MUTASE

描述（改编自申请人的摘要）： 该建议是开发新的药物靶点， 结核分枝杆菌的细胞壁 的组成部分之一 壁，半乳呋喃，是聚合物阿拉伯半乳聚糖的组成单元， 将分枝杆菌细胞壁的两个基本层连接在一起， 肽糖和分枝菌酸。 证据，涉及作用机制 一种已知的药物和一种温度敏感突变体的分离， 表明抑制阿拉伯半乳聚糖的生物合成将 阻止分枝杆菌细胞生长并可能导致细胞死亡。 作为 作为母基金的一部分，McNeils博士的团队克隆并表达了 UDP-吡喃半乳糖苷，呋喃半乳糖残基的供体。 的 福格蒂国际研究合作奖（FIRCA）的目的是 来获得这种酶的晶体结构， 加强父母补助金的具体目标，以确定其机制， 行动上 该补助金的其他目的是获得晶体结构 UDP-吡喃半乳糖苷与底物和底物类似物结合， 经定点突变得到其结构。 外交 詹姆斯·奈史密斯博士（苏格兰圣安德鲁斯大学） 已经结晶的大肠杆菌和小晶体的 肺炎克雷伯氏菌UDP-吡喃半乳糖突变酶。 使用同步加速器 Naismith博士已经收集了完整的X射线数据， E.大肠杆菌酶的分辨率为2.9（空间群P21，单位细胞 尺寸a = 71.12埃，B = 58.42埃，c = 97.89埃， α = γ = 90.0，β = 96.38_）。 奈史密斯博士的研究小组已经确定了一种 E.重金属浸泡大肠杆菌酶 实验和结晶硒代蛋氨酸E。大肠杆菌UDP-吡喃半乳糖 - 是的

DESCRIPTION (Adapted from the Applicant's Abstract): The overall purpose of this proposal is to develop new drug targets against the biosynthesis of the cell wall of Mycobacterium tuberculosis. One of the components of the wall, galactofuran, is an integral unit of the polymer arabinogalactan which links together the two essential layers of the mycobacterial cell wall, peptidoglyca and mycolic acids. Evidence, involving the mechanism of action of a know drug and the isolation of a temperature sensitive mutant, demonstrates that inhibition of the biosynthesis of arabinogalactan will stop mycobacterial cell growth and will probably result in cell death. As part of the parent grant, Dr McNeils' group has cloned and expressed UDP-galactopyranose mutase, the donor of galactofuranosyl residues. The aims of this Fogarty International Research Collaboration Award (FIRCA) are to obtain the crystal structure of this enzyme which will dramatically enhance the Specific Aim of the parent grant to determine its mechanism of action. Additional aims of this grant are to obtain the crystal structure of UDP-galactopyranose mutase bound to substrate and substrate analogues and to obtain its structure after sited-directed mutagenesis. The foreign collaborator, Dr. James Naismith (University of St. Andrews, Scotland) has already crystallized the Escherichia coli and has small crystals of the Klebsiella pneumonia UDP-galactopyranose mutases. Using synchrotron radiation, Dr. Naismith has collected complete x-ray data on crystals of the E. coli enzymes to a resolution of 2.9 Å (space group P21, unit cell dimensions of a = 71.12 angstrom, b = 58.42 angstrom, c = 97.89 angstrom, alpha = gamma = 90.0, beta = 96.38_). Dr. Naismith's group has identified a platinum derivative of the E. coli enzyme using heavy metal soaking experiments and crystallized selenomethionine E. coli UDP-galactopyranose mutase.