The structural and thermodynamic dissection of the interdomain cooperativity of human ACE

心血管疾病的经济负担令人震惊，据估计，英国每年的成本为500亿GB，欧盟为2500亿欧元，美国为1750亿美元。人体血管紧张素转换酶[ACE]广泛用于治疗心血管疾病，包括高血压、心力衰竭、冠状动脉疾病、纤维化和肾衰竭。ACE包含两个结构域(N-和C-)。然而，当前一代的血管紧张素转换酶抑制剂，是在20世纪70年代的S和80年代的S开发的，受到常见副作用的阻碍。ACE的N-结构域和C-结构域表现出不同的底物特异性。虽然市场上有许多阻断这两个结构域的ACE抑制剂，但没有药物选择性地抑制N-结构域，从而在心脏、肾脏和肺获得减轻纤维化和炎症的优势，而不会因为阻断C-结构域而产生副作用。这凸显了确定整个血管紧张素转换酶的分子结构和设计更安全、更有效的第二代血管紧张素转换酶抑制剂复合体/S的重要性。我们利用X射线结晶学技术成功地测定了人睾丸ACE(相当于体细胞ACE的C结构域)和体细胞ACE的N结构域(包括各种临床上重要的抑制剂以及新型结构域选择性抑制剂)的晶体结构，为基于真正结构的更好的ACE抑制剂的设计提供了平台。这是对ACE结构细节的重大突破，更重要的是，对ACE抑制机制的研究。这些重要的结果为一种更严格的方法铺平了道路，通过基于结构的新型结构域选择性抑制剂的药物设计路线来利用结构域之间的差异。因此，在理解ACE分子性质方面的持续努力为我们的团队提供了一个坚实的平台，用于我们提案中概述的新研究。我们建议的实验建立在以前和当前工作的基础上，旨在对全长ACE的结构进行研究。该提案将重点放在ACE的关键结构-功能研究上，这些研究涉及新的重要生物学问题，这些问题将对结合基础研究和翻译研究的新一代选择性ACE抑制剂的设计产生影响(从长远来看)。最终的长期目标将是设计针对ACE的N-末端或C-末端结构域的新化合物，期望这将提供副作用更少的选择性化合物。

The economic burden of cardiovascular illness is staggering, with estimated annual costs of £50 billion in the UK, Euro250 billion in the EU and $175 billion in the USA.Human somatic angiotensin-I converting enzyme [ACE, which contains two domains (N- and C-)] inhibitors are widely used to treat cardiovascular diseases, including high blood pressure, heart failure, coronary artery disease, fibrosis and kidney failure. However, current-generation ACE inhibitors, which were developed in the 1970's and 1980's, are hampered by common side effects. The N- and C-domains of ACE display different substrate specificities.While there are many ACE inhibitors on the market that block both domains, there are no drugs that selectively inhibit the N-domain and thereby accrue the advantages of reducing fibrosis and inflammation in the heart, kidney and lung, without the concomitant side effects induced by blockade of the C-domain. This underscores the importance of the determination of the molecular structure of entire ACE and the design of 2nd generation of new ACE-inhibitor complex/s that are safer and more effective. Our success in the determination of the crystal structure of human testis ACE (equivalent to the C-domain of somatic ACE) and the N-domain of somatic ACE (with various clinically important inhibitors as well as novel domain selective inhibitors) using the technique X-ray crystallography have provided the platform for true structure-based design of better ACE inhibitors. This is a significant breakthrough in terms of the structural details of ACE and, more importantly, the mechanism of ACE inhibition. These important results pave the way for a more rigorous approach exploiting the differences between the domains through a structure based drug design route of novel domain-selective inhibitors. Thus the sustained effort on understanding the 'hidden' molecular properties of ACE has provided a firm platform for our group for new studies as outlined in our proposal.Our proposed experiments that builds on a body of previous and current work are directed at structural study of the full-length ACE. The proposal has its focus on the crucial structure-function studies of ACE addressing new and important biological questions which will have implications (in the longer term) for the design of new generation of selective inhibitors of ACE combining basic and translational research. The ultimate longer term aim will be the design of new compounds that are specific for the N- or C-terminal domain of ACE with the expectation that this will provide selective compounds with fewer side effects.