CRYSTALLOGRAPHIC STRUCTURE DETERMINATION OF PRO REGION OF A LYTIC PROTEASE

A-裂解酶是一种由198个氨基酸组成的细菌丝氨酸蛋白酶。 这是由溶杆菌产酶分泌的。在分泌之前 以40kD前体的形式存在，由信号序列、PRO 地区，以及最终成为活跃的成熟领域 蛋白酶。多项研究表明，亲区域是 在体外和体内都需要正确折叠α-裂解酶 蛋白酶。在体内表达的没有PRO区域的蛋白水解酶 不是秘密的。在体外，变性的蛋白酶不会在没有 亲区的加入。PRO区域也是一个亚纳米分子 天然酶的抑制剂。很明显，这些互动 在PRO区域和成熟的蛋白水解酶之间是广泛的，可能 阐明了蛋白质是如何折叠的，以及为什么a-裂解物不能通过 它本身。我们将研究PRO区域的晶体。

a-lytic protease is a 198 amino acid bacterial serine protease that is secreted from Lysobacter enzymogenes. Before secretion it exists as a 40 kD precursor, consisting of a signal sequence, a PRO region, and the mature domain that eventually becomes the active protease. A number of studies have shown that the PRO region is required both in vitro and in vivo for proper folding of a-lytic protease. In vivo the protease expressed without the PRO region is not secreted. In vitro the denatured protease will not refold without the addition of PRO region. The PRO region is also a sub-nanomolar inhibitor of the native enzyme. It is clear that the interactions between the PRO region and the mature protease are extensive and may shed some light on how proteins fold and why a-lytic cannot fold by itself. We will be studying crystals of the PRO region.