Schlauderer G J, Proba K, Schulz G E
Institut für Organische Chemie und Biochemie Albertstr. Freiburg im Breisgau, Germany.
J Mol Biol. 1996 Feb 23;256(2):223-7. doi: 10.1006/jmbi.1996.0080.
Structural studies on unligated and ligated adenylate kinases have shown that two domains, LID and NMPbind, close over the bound substrates, ATP and AMP, respectively. These motions can be, but need not be independent from each other. Up to now, the known structures display only the states "both domains open", "both closed" and "NMP bind closed". In spite of numerous cocrystallization attempts with ATP, a crystalline state "LID closed" has not yet been produced. These experiences suggested that LID closure depends on a bound AMP molecule, in contrast to enzyme kinetic studies indicating a random-bi-bi mechanism. Using an inactive mutant of yeast adenylate kinase together with the ATP analogue AMPPCF2P, however, we have now crystallized an adenylate kinase in the LID closed state. The structure was established at 2.36 A resolution; it indicates that the domain motions occur largely independent from each other in agreement with the kinetic studies. As a side-result, we report the protein environment of the fluorine atoms of the bound ATP analogue.
对未结合和结合状态的腺苷酸激酶的结构研究表明，LID和NMPbind这两个结构域分别在结合的底物ATP和AMP上闭合。这些运动可以相互独立，但不一定必须如此。到目前为止，已知的结构仅显示出“两个结构域均开放”、“两个结构域均闭合”和“NMPbind结构域闭合”的状态。尽管进行了多次与ATP的共结晶尝试，但尚未产生“LID结构域闭合”的晶体状态。这些经验表明，与表明随机有序机制的酶动力学研究相反，LID结构域的闭合依赖于结合的AMP分子。然而，使用酵母腺苷酸激酶的无活性突变体与ATP类似物AMPPCF2P，我们现在已经使处于LID结构域闭合状态的腺苷酸激酶结晶。该结构在2.36埃分辨率下确定；它表明结构域运动在很大程度上相互独立，这与动力学研究结果一致。作为一个附带结果，我们报告了结合的ATP类似物中氟原子的蛋白质环境。
