Identification of the six ligands to manganese(II) in transition-state-analogue complexes of creatine kinase: oxygen-17 superhyperfine coupling from selectively labeled ligands.
Identification of the six ligands to manganese(II) in transition-state-analogue complexes of creatine kinase: oxygen-17 superhyperfine coupling from selectively labeled ligands.
复制标题
肌酸激酶过渡态类似物复合物中锰 (II) 的六种配体的鉴定：来自选择性标记配体的氧-17 超超精细偶联。
DOI：
10.1021/bi00565a002
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发表时间：
1980
期刊：
影响因子：
2.9
通讯作者：
Leyh,TS
中科院分区：
文献类型：
--
作者：
Reed,GH;Leyh,TS
乔治H. Reed* 和托马斯S. Leyh摘要：完整的协调方案锰（II）在过渡态类似物配合物与肌酸激酶已确定由电子顺磁共振（EPR）光谱。由于选择性标记的配体的nO的超超精细耦合Mn（II）的EPR谱中的扰动已被用来确定在金属离子的第一配位球的氧配体。结果表明，在酶-MnADP-甲酸盐-肌酸复合物中，Mn（Ⅱ）与ADP的α-和3-磷酸基上的氧配体、甲酸盐的羧酸基上的氧配体和3个水分子结合。在以硫氰酸根代替甲酸根作为稳定阴离子的络合物中，先前的红外实验[Reed，G. H、巴洛角H、& Burns，R.一、Jr.（1978年）。253，4153-4158]表明，来自硫氰酸盐的氮与Mn（II）结合。人们一直对金属离子-核苷酸复合物的结构以及各种酶在结合和催化中对复合物的特定结构的特异性感兴趣（Martin & Miriam，1979; Eckstein，1979）。在酶的活性位点上探测金属-核苷酸络合物结构的方法学方面有了一些新的进展。其中有基于（1）核苷酸的交换惰性Cr（III）和Co（III）（NH3）4络合物的方法（Cleland & Mildvan，1979; Danenberg & Cleland，1975; Cornelius et al.，1977; Dunaway-Mariano等人，1979），（2）软金属和硬金属离子对核苷硫代磷酸酯立体异构体的酶催化反应的立体选择性的影响（Jaffe & Cohn，1979; Pillai等人，1980）、（3）酶结合核苷酸的~（31）P NMR ~ 1研究（Cohn & Nageswara Rao，1979）和（4）晶体酶-金属-核苷酸的X射线衍射研究
George H. Reed* and Thomas S. Leyh abstract: The complete coordination scheme for Mn (II) in transition-state-analogue complexes with creatine kinase has been determined by electron paramagnetic resonance(EPR) spectroscopy. Perturbations in the EPR spectra for Mn (II) due to superhyperfine coupling to nOof selectively labeled ligands havebeen used to identify oxygen ligands in the first coordination sphere of the metal ion. The results show that in the complex of enzyme-MnADP-formate-creatine, Mn (II) is bound to oxygen ligands from both the a-and 3-phosphate groups of ADP, to an oxygen from the carboxylate group of formate, andto three water molecules. In the complex with thiocyanate replacing formate as the stabilizing anion, previous infrared experiments [Reed, G. H., Barlow, C. H., & Burns, R. A., Jr.(1978)/. Biol. Chem. 253, 4153-4158] indicated that the nitrogen from thiocyanate was bound to the Mn (II).There has been a continuing interest in the structures of metal ion-nucleotide complexes and in the specificity of various enzymes for particular structures of the complexes in binding and catalysis (Martin & Miriam, 1979; Eckstein, 1979). There have been several recent advances in methodology for probing thestructure of metal-nucleotide complexes at the active sites of enzymes. Among these are methods based on (1) the exchange-inert Cr (III) and Co (III)(NH3) 4 complexes of the nucleotides (Cleland & Mildvan, 1979; Danenberg & Cleland, 1975; Cornelius et al., 1977; Dunaway-Mariano et al., 1979),(2) soft and hard metal ion influences on the ste-reoselectivity of enzyme-catalyzed reactions of stereoisomers of nucleoside phosphorothioates (Jaffe & Cohn, 1979; Pillai et al., 1980),(3) 31P NMR1 studies of enzyme-bound nu-cleotides (Cohn & Nageswara Rao, 1979), and (4) X-ray diffraction studies of crystalline enzyme-metal-nucleotide