Eijsink V G, Veltman O R, Aukema W, Vriend G, Venema G
Department of Genetics, Center for Biological Sciences, University of Groningen, The Netherlands.
Nat Struct Biol. 1995 May;2(5):374-9. doi: 10.1038/nsb0595-374.
Thermolysin is a member of a family of homologous proteinases which differ in their resistance to thermally induced unfolding and subsequent autolytic degradation. Site-directed mutagenesis studies of the thermolysin-like proteinase (TLP) from Bacillus stearothermophilus (TLP-ste) show that its reduced resistance to thermally induced autolysis, as compared to thermolysin, is due to only some of the 44 naturally occurring amino-acid differences between them. In fact TLP-ste becomes more resistant than thermolysin by mutation of just a few of these amino-acids. The crucial differences are all localized to a solvent-exposed region in the N-terminal domain of TLP-ste.
嗜热菌蛋白酶是一类同源蛋白酶家族的成员，它们对热诱导的解折叠和随后的自溶降解的抗性不同。对嗜热脂肪芽孢杆菌的嗜热菌蛋白酶样蛋白酶（TLP-ste）进行的定点诱变研究表明，与嗜热菌蛋白酶相比，其对热诱导自溶的抗性降低仅归因于它们之间44个天然存在的氨基酸差异中的一部分。事实上，仅通过对其中少数几个氨基酸进行突变，TLP-ste就比嗜热菌蛋白酶更具抗性。关键差异都集中在TLP-ste N端结构域的一个溶剂暴露区域。
