Crystallographic Studies of p-Cresol Methylhydroxylase and Methylamine Dehydrogenase Enzyme Systems

将对两个细菌酶系统进行X射线衍射研究，每个系统都涉及氧化还原反应和电子转移反应。在3.0A分辨率下计算了对甲酚甲羟基酶晶体的电子密度图，并追踪了多肽链的路径。待氨基酸序列符合密度后，再对结构进行细化，研究底物与抑制剂的结合情况。合成了氨基花青素、甲胺脱氢酶及其分子间络合物的晶体。它们的结构将通过反常散射进行分析，多种同构置换和/或分子置换方法马修斯博士多年来一直致力于利用X射线衍射法研究生物大分子结构。他对b型细胞色素的研究在一定程度上导致了电子传输蛋白如何相互作用并将电子从一个传递到另一个的工作假说。他的方法是独一无二的，因为其中一个被研究的系统在同一分子中既有供体电子转移基团又有受体电子转移基团，而另一个系统包含一个新的假体基团。

X-ray diffraction studies will be carried out on two bacterial enzyme systems each involving oxidation-reduction and electron transfer reactions. An electron density map for crystals of p-cresol methylhydroxylase has been computed at 3.0 A resolution and the paths of the polypeptide chains have been traced. After the amino acid sequence has been fitted to the density, the structure will be refined and the binding of substrate and inhibitors studied. Crystals of amicyanin, methylamine dehydrogenase and of their intermolecular complex have been prepared. Their structures will be analyzed by anomalous scattering, multiple isomorphous replacement and/or molecular replacement methods Dr. Mathews has engaged in structural studies of biological macromolecules using X-ray diffraction methods for many years. His work on b type cytochromes has led in part to a working hypothesis of how electron transport proteins interact and pass electrons from one to another. His approach is unique in that one of the systems under study has both the donor and acceptor electron transfer groups in the same molecule, while the other system contains a novel prosthetic group.***//