Burnham Institute for Medical Research, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA,
Purinergic Signal. 2006 Jun;2(2):335-41. doi: 10.1007/s11302-005-5435-6. Epub 2006 Jun 17.
Our knowledge of the structure and function of alkaline phosphatases has increased greatly in recent years. The crystal structure of the human placental isozyme has enabled us to probe salient features of the mammalian enzymes that differ from those of the bacterial enzymes. The availability of knockout mice deficient in each of the murine alkaline phosphatase isozymes has also given deep insights into their in vivo role. This has been particularly true for probing the biological role of bone alkaline phosphatase during skeletal mineralization. Due to space constraints this mini-review focuses exclusively on structural and functional features of mammalian alkaline phosphatases as identified by crystallography and probed by site-directed mutagenesis and kinetic analysis. An emphasis is also placed on the substrate specificity of alkaline phosphatases, their catalytic properties as phosphohydrolases as well as phosphodiesterases and their structural and functional relatedness to a large superfamily of enzymes that includes nucleotide pyrophosphatase/phosphodiesterase.
近年来，我们对碱性磷酸酶的结构和功能的了解有了很大的提高。人胎盘同工酶的晶体结构使我们能够探测哺乳动物酶与细菌酶不同的显著特征。缺乏每种鼠碱性磷酸酶同工酶的基因敲除小鼠的可用性也深入了解了它们在体内的作用。在探测骨骼矿化过程中骨碱性磷酸酶的生物学作用时尤其如此。由于篇幅限制，本篇迷你评论仅专注于晶体学鉴定的哺乳动物碱性磷酸酶的结构和功能特征，并通过定点突变和动力学分析进行探究。本文还强调了碱性磷酸酶的底物特异性、作为磷酸水解酶以及磷酸二酯酶的催化特性，以及它们与包括核苷酸焦磷酸酶/磷酸二酯酶在内的大型酶超家族的结构和功能相关性。
