Warner Fiona J, Guy Jodie L, Lambert Dan W, Hooper Nigel M, Turner Anthony J
1Baker Heart Research Institute, Peptide Biology, 3004 Melbourne, Victoria Australia.
2Proteolysis Research Group, School of Biochemistry and Microbiology, University of Leeds, LS2 9JT Leeds, UK.
Lett Pept Sci. 2003;10(5):377-385. doi: 10.1007/BF02442567.
Angiotensin converting enzyme-2 (ACE2) is a recently described homologue of the vasoactive peptidase, angiotensin converting enzyme (ACE). Like ACE, ACE2 is an integral (type I) membrane zinc metallopeptidase, which exists as an ectoenzyme. ACE2 is less widely distributed than ACE in the body, being expressed at highest concentrations in the heart, kidney and testis. ACE2 also differs from ACE in its substrate specificity, functioning exclusively as a carboxypeptidase rather than a peptidyl dipeptidase. A key role for ACE2 appears to be emerging in the conversion of angiotensin II to angiotensin (1-7), allowing it to act as a counter-balance to the actions of ACE. ACE2 has been localised to the endothelial and epithelial cells of the heart and kidney where it may have a role at the cell surface in hydrolysing bioactive peptides such as angiotensin II present in the circulation. A role for ACE2 in the metabolism of other biologically active peptides also needs to be considered. ACE2 also serendipitously appears to act as a receptor for the severe acute respiratory syndrome (SARS) coronavirus. Studies using mice, and other emerging studies and, have revealed that ACE2 has important functions in cardiac regulation and diabetes. Together with its role as a SARS receptor, ACE2 is therefore likely to be an important therapeutic target in a diverse range of disease states.
血管紧张素转换酶2（ACE2）是最近发现的血管活性肽酶血管紧张素转换酶（ACE）的同源物。与ACE一样，ACE2是一种完整的（I型）膜锌金属肽酶，以胞外酶形式存在。ACE2在体内的分布不如ACE广泛，在心脏、肾脏和睾丸中表达浓度最高。ACE2在底物特异性方面也与ACE不同，它仅作为羧肽酶发挥作用，而不是肽基二肽酶。ACE2在将血管紧张素II转化为血管紧张素（1-7）的过程中似乎正在发挥关键作用，使其能够作为ACE作用的一种平衡力量。ACE2已定位在心脏和肾脏的内皮细胞和上皮细胞中，在细胞表面可能具有水解循环中存在的生物活性肽（如血管紧张素II）的作用。还需要考虑ACE2在其他生物活性肽代谢中的作用。ACE2偶然还似乎充当严重急性呼吸综合征（SARS）冠状病毒的受体。使用小鼠的研究以及其他新出现的研究表明，ACE2在心脏调节和糖尿病中具有重要功能。因此，连同其作为SARS受体的作用，ACE2很可能是多种疾病状态下的一个重要治疗靶点。
