Structures and Reactivities of Quaternary Metal Complexes as Enzyme Models

从一个角度来看，利用金属酶-辅因子-基底中间复合体的结构和反应机制，我们研究了作为生物模型的长期和四个复合体系统的结构、稳定性和反应性。交替Cu （II）复合体中的芳香环堆叠[Cu （bpy） （L-Trp） ClO_4]和[Cu （bpy）（L-Tyr）ClO_4]·2H_2O （bpy = 2， 2'-双吡啶; Trp =tryptophan ; Tyr = Tyrosine），可以在bpy和Trp和Tyr侧链芳香环之间的固态状态中建立，相应地，由X射线晶体结构分析。Upon phosphorylation of the Tyr phenol OH group， the phenol ring is involved in electrostatic interactions with the charged side group of arginine or lysine coordinated to the same Cu （II） ion。结果提出了一项关于Tyr磷酸化在蛋白质中导致在氨基酸酯组之间的侧链交互模式中发生变化的可能性，并因此导致蛋白质修饰性变化的结果。 ... More 铂DNA干扰器之间的沉积形成[Pt （L） （en）] （L = bpy， 1，10-苯甲酸（plien）， 3， 4， 7，8四甲基-1，10-苯甲酸（Me_4 phen） ）和单核肽（NMP = AMP， GMP， CMP）已通过光谱学方法研究。[pt（Me_4phen） （en）]由于最大的羟基区域已经发现，可以形成NMP中最稳定的添加物，主要通过L和NMP的基本活力。它包括NMP磷酸组和Pt^<2+>之间的电静态交互，或与NH_2组对增加稳定性的协调作用。永久和四季铜（II）复合体的结构和稳定性，使一个彼得林协同剂模型已通过光谱学方法和潜力进行了调查。在L =咪唑（im）、NH_3或N_3^-中找到了Cu （bpy） （PC） （PC） （im）（im）（PC） （im）系统的稳定常数，即苯丙氨酸羟基化酶活性位点模型以L =咪唑（im）、NH_3或N_3^-的形式，以及Cu （bpy） （PC） （im）系统在25 ℃ C和I = 0.1 M （KNO_3）的pH值被成功地检测到。Cu （bpy）^<2+>之间的还原反应和四氢磷素是由光谱学和色谱学方法跟踪的，据证实，磷素被氧化成二氢形式，含有二氧化合物的消费。Less（低）

With a view to elucidating the structures and reaction mechanisms of metalloenzyme-cofactor-substrate intermediate complexes, we investigated the structures, stabilities, and reactivities of ternary and quaternary complex systems as biological models.1. Aromatic ring stacking in ternary Cu (II) complexes, [Cu (bpy) (L-Trp) ClO_4]and[Cu (bpy) (L-Tyr)ClO_4]・2H_2O (bpy = 2, 2'-bipyridine ; Trp =tryptophan ; Tyr = tyrosine), has been established in the solid state between bpy and the side chain aromatic ring of Trp and Tyr, respectively, by X-ray crystal structure analysis. Upon phosphorylation of the Tyr phenol OH group, the phenol ring is involved in electrostatic interactions with the charged side group of arginine or lysine coordinated to the same Cu (II) ion. The result suggests the possibility that Tyr phosphorylation in proteins causes the change in the mode of interactions between the side chain groups of amino acid residues and thus gives rise to protein conformational changes.2. … More Adduct formation between platinum DNA intercalators[Pt (L) (en)] (L = bpy, 1, 10-phenanthroline (plien), 3, 4, 7, 8tetramethyl-1, 10-phenanthroline (Me_4phen) ) and mononucleotides (NMP = AMP, GMP, CMP) has been studied by spectroscopic methods. [pt (Me_4phen) (en)]with the largest hydrophobic area has been found to form the most stable adducts with NMP mainly through the stacking between L and the base moiety of NMP. It was concluded that the electrostatic interactions between the NMP phosphate group and Pt^<2+> or the coordinated en NH_2 group contribute to the adduct stability.3. Structures and stabilities of ternary and quaternary Cu (II) complexes involving a pterin cofactor model have been investigated by spectroscopic methods and potentiometry. Cu (bpy) (PC) (PC pterin-6-carboxylate) as a phenylalanine hydroxylase active site model was found to form quaternary complexes with L = imidazole (im), NH_3, or N_3^-, and the stability constants for the Cu (bpy) (PC) (im) system were successfully detemined by pH titrations at 25ﾟC and I = 0.1 M (KNO_3). The redox reactions between Cu (bpy)^<2+> and a tetrahydropterin were followed by spectroscopic and chromatographic methods, which revealed that the pterin is oxided to the dihydro form with, consumption of dioxygen. Less