Induced fit in arginine kinase.
Induced fit in arginine kinase.
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精氨酸激酶的诱导拟合。
DOI：
10.1016/s0006-3495(00)76706-3
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发表时间：
2000
影响因子：
3.4
通讯作者：
Chapman,MS
中科院分区：
文献类型：
--
作者：
Zhou,G;Ellington,WR;Chapman,MS
肌酸激酶(CK)和精氨酸激酶(AK)是两种相关的酶，它们可逆地将磷酸基转移到胍基化合物和ADP之间。在缓冲ATP能量水平的过程中，它们是能量代谢的中心，也是经典酶学的范例。CK的开放无底物结构和AK的闭合底物结合结构的比较发现了差异，这与先前底物诱导构象变化的生物物理证据相一致。大小磁区经历13°铰接旋转。在底物存在的情况下，几个环变得有序并采用不同的位置，其中一个(残基309-319)移动15？以折叠到底物上。构象变化似乎在对齐两种底物以进行催化时是必要的，只有在可能发生生产性的磷酰化转移时才配置活性部位，并从活性部位排除水以避免浪费的ATP水解。
Creatine kinase (CK) and arginine kinase (AK) are related enzymes that reversibly transfer a phosphoryl group between a guanidino compound and ADP. In the buffering of ATP energy levels, they are central to energy metabolism and have been paradigms of classical enzymology. Comparison of the open substrate-free structure of CK and the closed substrate-bound structure of AK reveals differences that are consistent with prior biophysical evidence of substrate-induced conformational changes. Large and small domains undergo a hinged 13° rotation. Several loops become ordered and adopt different positions in the presence of substrate, including one (residues 309–319) that moves 15Å to fold over the substrates. The conformational changes appear to be necessary in aligning the two substrates for catalysis, in configuring the active site only when productive phosphoryl transfer is possible, and excluding water from the active site to avoid wasteful ATP hydrolysis.