Stability studies of amino acid substitutions at tyrosine 27 of the staphylococcal nuclease beta-barrel.
Stability studies of amino acid substitutions at tyrosine 27 of the staphylococcal nuclease beta-barrel.
复制标题
葡萄球菌核酸酶 β-桶酪氨酸 27 处氨基酸取代的稳定性研究。
DOI：
10.1021/bi970876r
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Fox,RO
中科院分区：
文献类型：
--
作者：
Bhat,MG;Ganley,LM;Ledman,DW;Goodman,MA;Fox,RO
为了帮助确定葡萄球菌核酸酶β-Barrel内的侧链相互作用对其全局稳定性的影响程度，为残基27产生了一整套点突变。在盐酸胍的溶剂变性过程中监测了内源性色氨酸荧光，并用于计算每个突变体的Δ、GH_2O展开和m值。在野生型蛋白中，残基27是一种酪氨酸，它位于I‘β-Turn的第一位，参与疏水相互作用和侧链到侧链的氢键。突变残基的疏水性被发现是决定这一系列核酸酶突变中整体蛋白质稳定性的主导因素。
In order to help determine the extent to which side chain interactions within the staphylococcal nuclease β-barrel affect its global stability, a full set of point mutants was generated for residue 27. Intrinsic tryptophan fluorescence was monitored during solvent denaturation with guanidine hydrochloride (GuHCl) and was used to calculate ΔGH2Ounfoldingandmvalues for each mutant. In the wild type protein, residue 27 is a tyrosine which is at the first position of a type I‘ β-turn, and which participates in both hydrophobic interactions and side chain to side chain hydrogen bonding. The hydrophobicity of the mutant residue was found to be the dominant factor in determining global protein stability within this series of nuclease mutants.