White S P, Scott D L, Otwinowski Z, Gelb M H, Sigler P B
Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511.
Science. 1990 Dec 14;250(4987):1560-3. doi: 10.1126/science.2274787.
The crystal structure of a complex between a phosphonate transition-state analogue and the phospholipase A2 (PLA2) from Naja naja atra venom has been solved and refined to a resolution of 2.0 angstroms. The identical stereochemistry of the two complexes that comprise the crystal's asymmetric unit indicates both the manner in which the transition state is stabilized and how the hydrophobic fatty acyl chains of the substrate are accommodated by the enzyme during interfacial catalysis. The critical features that suggest the chemistry of binding and catalysis are the same as those seen in the crystal structure of a similar complex formed with the evolutionarily distant bee-venom PLA2.
已解析并精修了一种膦酸酯过渡态类似物与眼镜蛇毒磷脂酶A2（PLA2）形成的复合物的晶体结构，分辨率达到2.0埃。构成晶体不对称单元的两个复合物具有相同的立体化学结构，这既表明了过渡态的稳定方式，也显示了在界面催化过程中底物的疏水脂肪酰链是如何被酶容纳的。表明结合和催化化学性质的关键特征与在与进化关系较远的蜂毒PLA2形成的类似复合物的晶体结构中所观察到的特征相同。
