Purification and characterization of the periplasmic lysine-, arginine-, ornithine-binding protein (LAO) from Salmonella typhimurium.
Purification and characterization of the periplasmic lysine-, arginine-, ornithine-binding protein (LAO) from Salmonella typhimurium.
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DOI：
10.1016/s0021-9258(19)36743-2
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发表时间：
1992-10
期刊：
影响因子：
--
通讯作者：
K. Nikaido;G. Ames
中科院分区：
文献类型：
--
作者：
K. Nikaido;G. Ames
鼠伤寒沙门氏菌的赖氨酸，精氨酸，鸟氨酸结合蛋白（LAO）已被纯化到同质性和特点。通过平衡透析测定法测定L-精氨酸、L-赖氨酸和L-鸟氨酸的解离常数（KD）分别为14、15和29 nM。发现L-组氨酸是相对良好的配体（KD，500 nM）。已经开发了用于分离配体与未配体的LAO、用于估计结合配体和用于解配体的LAO的方法。配体和未配体的LAO显示出具有不同的UV光谱。UV光谱也随基材的性质而变化。底物类似物的抑制研究产生的信息有助于了解配体结合口袋的性质。
The lysine-, arginine-, ornithine-binding protein (LAO) from Salmonella typhimurium has been purified to homogeneity and characterized. The dissociation constants (KD) were determined by equilibrium dialysis assay to be 14, 15, and 29 nM for L-arginine, L-lysine, and L-ornithine respectively. L-Histidine was found to be a relatively good ligand (KD, 500 nM). Methods have been developed for the separation of liganded from unliganded LAO, for the estimation of bound ligand, and for unliganding LAO. Liganded and unliganded LAO are shown to have distinct UV spectra. The UV spectrum also varies with the nature of the substrate. Inhibition studies with substrate analogs yielded information useful for understanding the nature of the ligand-binding pocket.