Tang J, Wong R N
J Cell Biochem. 1987 Jan;33(1):53-63. doi: 10.1002/jcb.240330106.
Aspartic proteases (EC3.4.23) are a group of proteolytic enzymes of the pepsin family that share the same catalytic apparatus and usually function in acid solutions. This latter aspect limits the function of aspartic proteases to some specific locations in different organisms; thus the occurrence of aspartic proteases is less abundant than other groups of proteases, such as serine proteases. The best known sources of aspartic proteases are stomach (for pepsin, gastricsin, and chymosin), lysosomes (for cathepsins D and E), kidney (for renin), yeast granules, and fungi (for secreted proteases such as rhizopuspepsin, penicillopepsin, and endothiapepsin). These aspartic proteases have been extensively studied for their structure and function relationships and have been the topics of several reviews or monographs (Tang: Acid Proteases, Structure, Function and Biology. New York: Plenum Press, 1977; Tang: J Mol Cell Biochem 26:93-109, 1979; Kostka: Aspartic Proteinases and Their Inhibitors. Berlin: Walter de Gruyter, 1985). All mammalian aspartic proteases are synthesized as zymogens and are subsequently activated to active proteases. Although a zymogen for a fungal aspartic protease has not been found, the cDNA structure of rhizopuspepsin suggests the presence of a "pro" enzyme (Wong et al: Fed Proc 44:2725, 1985). It is probable that other fungal aspartic proteases are also synthesized as zymogens. It is the aim of this article to summarize the major models of structure-function relationships of aspartic proteases and their zymogens with emphasis on more recent findings. Attempts will also be made to relate these models to other aspartic proteases.
天冬氨酸蛋白酶（EC3.4.23）是胃蛋白酶家族的一组蛋白水解酶，它们具有相同的催化机制，通常在酸性溶液中发挥作用。后一个方面将天冬氨酸蛋白酶的功能限制在不同生物体中的某些特定位置；因此，天冬氨酸蛋白酶的出现不如其他蛋白酶组丰富，如丝氨酸蛋白酶。天冬氨酸蛋白酶最著名的来源是胃（胃蛋白酶、胃凝乳酶和凝乳酶）、溶酶体（组织蛋白酶D和E）、肾脏（肾素）、酵母颗粒和真菌（分泌的蛋白酶，如根霉胃蛋白酶、青霉胃蛋白酶和内孢霉胃蛋白酶）。这些天冬氨酸蛋白酶因其结构与功能的关系而受到广泛研究，并成为多篇综述或专著的主题（唐：《酸性蛋白酶，结构、功能与生物学》。纽约：普伦出版社，1977年；唐：《分子与细胞生物化学杂志》26:93 - 109，1979年；科斯特卡：《天冬氨酸蛋白酶及其抑制剂》。柏林：瓦尔特·德·格鲁伊特出版社，1985年）。所有哺乳动物天冬氨酸蛋白酶都以酶原形式合成，随后被激活成为活性蛋白酶。虽然尚未发现真菌天冬氨酸蛋白酶的酶原，但根霉胃蛋白酶的cDNA结构表明存在一种“前体”酶（王等人：《联邦会议记录》44:2725，1985年）。很可能其他真菌天冬氨酸蛋白酶也以酶原形式合成。本文的目的是总结天冬氨酸蛋白酶及其酶原结构 - 功能关系的主要模型，重点是最新发现。还将尝试将这些模型与其他天冬氨酸蛋白酶联系起来。
