The effect of introducing small cavities on the allosteric inhibition of phosphofructokinase from Bacillus stearothermophilus.
The effect of introducing small cavities on the allosteric inhibition of phosphofructokinase from Bacillus stearothermophilus.
复制标题
引入小空腔对嗜热脂肪芽孢杆菌磷酸果糖激酶变构抑制的影响。
DOI：
10.1016/j.abb.2016.06.022
复制
发表时间：
2016
影响因子：
3.9
通讯作者：
Reinhart,GregoryD
中科院分区：
文献类型：
--
作者：
Whitaker,AmyM;Reinhart,GregoryD
嗜热脂肪芽孢杆菌（Bacillus stearothermophilus，BsPFK）的磷酸果糖激酶-1（phosphofructokinase-1，PFK）的配体果糖-6-磷酸（Fru-6-P）和磷酸烯醇丙酮酸（phospho（enol）pyruvate，PEP）之间的变构偶联自由能是由焓和熵补偿引起的。在BsPFK中，定义抑制的正耦合自由能与负焓项的符号相反，因此由负熵项的较大绝对值确定。制备BsPFK的变体以确定向结构中添加小空腔对酶的变构功能的影响。BsPFK Ile →瓦尔（含空腔）突变体具有不同的PEP和Fru-6-P之间的偶联自由能值，表明修饰改变了PEP作为抑制剂的有效性。值得注意的是，突变I153 V对PEP的抑制程度具有实质性的积极影响。范特霍夫分析确定，这是熵-焓补偿减小的结果，与熵项相比，焓项的变化更大。
The allosteric coupling free energy between ligands fructose-6-phosphate (Fru-6-P) and phospho(enol)pyruvate (PEP) for phosphofructokinase-1 (PFK) from the moderate thermophile,Bacillus stearothermophilus(BsPFK), results from compensating enthalpy and entropy components. In BsPFK the positive coupling free energy that defines inhibition is opposite in sign from the negative enthalpy term and is therefore determined by the larger absolute value of the negative entropy term. Variants of BsPFK were made to determine the effect of adding small cavities to the structure on the allosteric function of the enzyme. The BsPFK Ile → Val (cavity containing) mutants have varied values for the coupling free energy between PEP and Fru-6-P, indicating that the modifications altered the effectiveness of PEP as an inhibitor. Notably, the mutation I153V had a substantial positive impact on the magnitude of inhibition by PEP. Van't Hoff analysis determined that this is the result of decreased entropy-enthalpy compensation with a larger change in the enthalpy term compared to the entropy term.
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影响因子：
13.8
作者：
Fenton, Aron W.
通讯作者：
Fenton, Aron W.
影响因子：
3.9
作者：
V. L. Tlapak-Simmons;G. Reinhart
通讯作者：
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影响因子：
64.8
作者：
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通讯作者：
HUDSON, PJ
DOI：
10.1073/pnas.050588097
发表时间：
2000-04-11
影响因子：
11.1
作者：
Kimmel, JL;Reinhart, GD
通讯作者：
Reinhart, GD
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影响因子：
2.9
作者：
Riley-Lovingshimer,MR;Reinhart,GD
通讯作者：
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