Structure-function studies on human Angiotensin-I converting enzyme (ACE)

血管紧张素转换酶[ACE]抑制剂含有N和C两个结构域，广泛用于治疗心血管疾病，包括高血压、心力衰竭、冠心病、纤维化和肾功能衰竭。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-结构域具有不同的底物特异性。虽然市场上有许多ACE抑制剂可以阻断这两个结构域，但还没有药物选择性地抑制N结构域，从而获得减少心脏、肾脏和肺的纤维化和炎症的优势，而不会因为阻断C结构域而产生伴随的副作用。这凸显了确定血管紧张素转换酶的三维结构和设计更安全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。我们成功地测定了人体睾丸ACE(相当于体细胞ACE的C结构域)和体细胞ACE的N结构域(血管紧张素转换酶[ACE，包含N和C两个结构域])的晶体结构，这些抑制剂被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、纤维化和肾功能衰竭。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-结构域具有不同的底物特异性。虽然市场上有许多ACE抑制剂可以阻断这两个结构域，但还没有药物选择性地抑制N结构域，从而获得减少心脏、肾脏和肺的纤维化和炎症的优势，而不会因为阻断C结构域而产生伴随的副作用。这凸显了确定血管紧张素转换酶的三维结构和设计更安全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。我们成功地利用X射线结晶学测定了人睾丸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。这在蛋白水解酶的结构生物学以及更重要的ACE抑制机制方面是一项重大突破。这为一种更严格的方法铺平了道路，通过基于结构的新域选择性抑制剂的药物设计方法来利用结构域之间的差异。因此，对ACE的持续努力为我们小组的新研究提供了坚实的平台。我们提出的实验是在前人和当前工作的基础上进行的，旨在结合对一个重要医学问题的基础研究和翻译研究，对全长体细胞ACE的结构和ACE与结构域选择性抑制剂的复合体的晶体结构进行研究。从长远来看，该应用寻求利用详细的结构知识来合成新的血管紧张素转换酶抑制剂，目的是提供更好的药物来治疗心血管疾病，特别是高血压和纤维化。一个关键特征将是针对ACE的N-末端或C-末端结构域的化合物的设计，期望这将提供副作用更少的选择性化合物用于治疗。

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 3D structure of ACE and the design of 2nd generation 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 (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 3D structure of ACE and the design of 2nd generation 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 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 biology of the protease and, more importantly, the mechanism of ACE inhibition. This paves the way for a more rigorous approach exploiting the differences between the domains through a structure based drug design approach of novel domain-selective inhibitors. Thus the sustained effort on ACE has provided a firm platform for our group for the new studies. Our proposed experiments that builds on a body of previous and current work are directed at structural study of the full-length somatic ACE and crystal structures of complexes of ACE with domain selective inhibitors combining basic and translational research on an important medical problem. In the longer term, the application seeks to exploit detailed structural knowledge for the synthesis of new ACE inhibitors with the aim of providing better drugs for the treatment of cardiovascular diseases in particular hypertension and fibrosis. A key feature will be the design of compounds that are specific for the N- or C-terminal domain of ACE with the expectation that this will provide selective compounds for therapy with fewer side effects.