Do monomeric vs dimeric forms of MAO-A make a difference? A direct comparison of the catalytic properties of rat and human MAO-A's.
Do monomeric vs dimeric forms of MAO-A make a difference? A direct comparison of the catalytic properties of rat and human MAO-A's.
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MAO-A 的单体形式与二聚形式有区别吗？
DOI：
10.1007/s00702-007-0678-8
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
Edmondson,DE
中科院分区：
文献类型：
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作者：
Wang,J;Edmondson,DE
人MAO-A和大鼠MAO-A的最新晶体学结构表明，人MAO-A是单体，而大鼠MAO-A是二聚体，尽管它们具有约90%的序列同一性。这种结构差异的功能意义尚不清楚。因此，本文采用生物化学方法研究了寡聚状态对人和大鼠MAO-A功能特性的影响。数据表明：1）MAO-A的二聚化增加了其结构稳定性; 2）动力学性质的差异可能是由于人和大鼠酶的寡聚状态的差异导致的活性位点结构的差异造成的; 3）QSAR研究表明大鼠MAO-A以及人MAO-A催化通过质子提取机制发生，并且两种酶的底物结合相似。
The recent crystallographic structures of human MAO-A and rat MAO-A have shown that human MAO-A is monomeric whereas rat MAO-A is a dimer, even though they share ∼90% sequence identity. The functional significance of this structural difference is unknown. Therefore, biochemical approaches in this paper were performed to investigate the influence of oligomeric state on functional properties of human and rat MAO-A’s. The data show that 1) dimerization of MAO-A increases its structural stability; 2) the differences in kinetic properties may be caused by differences in active site structures as a result of differences in oligomeric states of the human and the rat enzymes; 3) QSAR studies show rat MAO-A as well as human MAO-A catalysis occur via proton abstraction mechanisms, and the binding of substrates is similar for both enzymes.