Recruiting Zn2+ to mediate potent, specific inhibition of serine proteases
Recruiting Zn2+ to mediate potent, specific inhibition of serine proteases
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DOI：
10.1006/jmbi.1999.3071
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发表时间：
1999-09-24
影响因子：
5.6
通讯作者：
Luong, C
中科院分区：
文献类型：
--
作者：
Katz, BA;Luong, C
丝氨酸蛋白酶作为无所不在的生物过程的调节因子，在表达或调节不当时可引起疾病状态，因此是药物抑制的合理靶点。最近，我们描述了一种新的抑制机制，适用于开发有效的、选择性的小分子丝氨酸蛋白酶抑制剂，这些抑制剂可以招募生理性的Zn2+来介导高亲和力（亚纳摩尔）结合。为了证明Zn2+介导的丝氨酸蛋白酶抑制剂可以对特定靶标产生选择性的一些结构原理，本文确定并描述了凝血酶-BABIM-Zn2+、-酮-BABIM-Zn2+和-半BABIM-Zn2+的结构(其中BABIM是双（5-氨基-2-苯并咪唑）甲烷，酮-BABIM是双（5-氨基-2-苯并咪唑）甲烷酮。半babim为（5-氨基-2-苯并咪唑）（2-苯并咪唑），并与相应的胰蛋白酶抑制剂- zn2 +配合物进行比较。抑制剂的结合由两个苯并咪唑氮原子配位的Zn离子、N-His57（epsilon 2）和O-Ser195（γ）介导。在选定的pH值下测定了无Zn2+胰蛋白酶- babim和-半babim的结构，并与相应的Zn2+介导配合物进行比较。为了评估利用Zn2+作为共抑制剂的一些重要生理参数，我们测定了胰蛋白酶-酮- babim在不同PH值和[Zn2+]值下的晶体结构。Zn2+对二元胰蛋白酶-酮- babim复合物的K-d值估计为
As regulators of ubiquitous biological processes, serine proteases can cause disease states when inappropriately expressed or regulated, and are thus rational targets for inhibition by drugs. Recently we described a new inhibition mechanism applicable for the development of potent, selective small molecule serine protease inhibitors that recruit physiological Zn2+ to mediate high affinity (sub-nanomolar) binding. To demonstrate some of the structural principles by which the selectivity of Zn2+ mediated serine protease inhibitors can be developed toward or against a particular target, here we determine and describe the structures of thrombin-BABIM-Zn2+, -keto-BABIM-Zn2+, and -hemi-BABIM-Zn2+ (where BABIM is bis(5-amidino-2-benzimidazolyl)methane, keto-BABIM is bis(5-amidino-2-benzimidazolyl)methane ketone, and hemi-BABIM is (5-amidino-2-benzimidazolyl)(2-benzimidazolyl) and compare them with the corresponding trypsin-inhibitor-Zn2+ complexes. Inhibitor binding is mediated by a Zn ion tetrahedrally coordinated by two benzimidazole nitrogen atoms of the inhibitor, by N-His57(epsilon 2), and by O-Ser195(gamma). The structures of Zn2+-free trypsin-BABIM and -hemi-BABIM were also determined at selected pH values for comparison with the corresponding Zn2+-mediated complexes. To assess some of the physiological parameters important for harnessing Zn2+ as a co-inhibitor, crystal structures at multiple PH and [Zn2+] values were determined for trypsin-keto-BABIM. The K-d value of Zn2+ for the binary trypsin-keto-BABIM complex was estimated to be