鲍氏芽胞杆菌重组亮氨酰氨基肽酶的生物物理特性分析。

Biophysical characterization of a recombinant leucyl aminopeptidase from Bacillus kaustophilus.

机构信息

Department of Applied Chemistry, National Chiayi University, Chiayi, Taiwan.

出版信息

Biochemistry (Mosc). 2010 May;75(5):642-7. doi: 10.1134/s0006297910050159.

PMID:20632945

Abstract

The biophysical properties of Bacillus kaustophilus leucyl aminopeptidase (BkLAP) were examined in terms of analytical ultracentrifugation, fluorescence spectroscopy, and circular dichroism. By using the analytical ultracentrifuge, we demonstrated that tetrameric BkLAP exists as the major form in solution at protein concentration of 1.5 mg/ml at pH 8.0. The native enzyme started to unfold beyond ~1 M GdnHCl and reached an unfolded intermediate with GdnHCl at 1.8 M. Thermal unfolding of BkLAP was found to be highly irreversible and led to a marked formation of aggregates.

摘要

我们通过分析超速离心、荧光光谱和圆二色性研究了解淀粉芽孢杆菌亮氨酰氨基肽酶（BkLAP）的生物物理性质。在蛋白质浓度为 1.5mg/ml、pH8.0 的条件下，分析超速离心实验表明四聚体 BkLAP 是溶液中的主要形式。天然酶在超过~1M 的 GdnHCl 时开始展开，并在 1.8M 时达到具有GdnHCl的展开中间态。BkLAP 的热展开是高度不可逆的，并导致明显的聚集物形成。