Crystallographic Study of a Quinoprotein Electron Transfer System: Methylamine Dehydrogenase

醌蛋白电子转移系统的晶体学研究：甲胺脱氢酶

• 批准号: 9119789
• 负责人: F. Mathews
• 金额: $ 36万
• 依托单位: Washington University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-03-01 至 1995-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9119789&HistoricalAwards=false
• 关键词: Crystallographic; Study; Quinoprotein; Electron; Transfer

Structural studies will be carried out on the quinoprotein-electron transfer system methylamine dehydrogenase (MADH) from Paracoccus denitrificans by the methods of x-ray diffraction. Three proteins are involved in this system, MADH, amicyanin and cytochrome c551i. MADH is a dimer of 124 kDa and contains the unusual cofactor tryptophan tryptophylquinone. Amicyanin is a blue copper protein of 12.5 kDa which interacts specifically with MADH. Cytochrome c551i is a 22 kDa protein which accepts electrons from amicyanin and transfers them via another cytochrome to a terminal oxidase. Crystals have been prepared of MADH, amicyanin, the binary complex of MADH with amicyanin and of the ternary complex of MADH, amicyanin and cytochrome c551i. The structures of MADH and the binary complex have been solved by molecular replacement to 2.8 A and 2.5 A resolution, respectively. The structures of the remaining crystal types and of the cytochrome by itself will be determined. The structures of all crystal types will be refined by simulated annealing and energy minimization. These structures will be carefully analyzed using molecular graphics to determine the catalytic mechanisms and details of the electron transfer processes.

结构研究将在 醌蛋白电子转移系统甲胺脱氢酶 用X-射线法从嗜热副球菌中分离MADH 衍射法 该系统涉及三种蛋白质，MADH， amicyanin和细胞色素c551 i。 MADH是124 kDa的二聚体， 含有不寻常的辅助因子色氨酸醌。 Amicyanin是一种12.5 kDa的蓝色铜蛋白， 特别是与MADH。 细胞色素c551 i是一种22 kDa的蛋白质 它接受来自amicyanin的电子， 另一种细胞色素转化为末端氧化酶。 已经制备了MADH，amicyanin，二元 MADH与amicyanin的络合物和MADH与amicyanin的三元络合物的络合物 MADH、amicyanin和细胞色素c551 i。 MADH的结构和 二元复合物已经通过分子置换来解决， 2.8 A和2.5 A分辨率。 的结构 剩余的晶体类型和细胞色素本身将是 测定 所有晶体类型的结构都将被细化 通过模拟退火和能量最小化。 这些结构 将使用分子图形进行仔细分析，以确定 电子转移的催化机理和细节 流程.