Temperature dependence of molecular interactions involved in defining stability of glutamine binding protein and its complex with L-glutamine.
Temperature dependence of molecular interactions involved in defining stability of glutamine binding protein and its complex with L-glutamine.
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DOI：
10.1021/bi201494h
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发表时间：
2012-01-17
期刊：
影响因子：
2.9
通讯作者：
Tjandra, Nico
中科院分区：
文献类型：
--
作者：
Pistolesi, Sara;Tjandra, Nico
从核磁共振（NMR）弛豫数据中得到的动力学参数的温度依赖性与所研究的系统的构象熵有关。这提供了诸如配体结合的大分子稳定性和热力学的信息。我们研究了谷氨酰胺结合蛋白（GlnBP），周质结合蛋白（PBP）高度特异性的L-谷氨酰胺与其ABC转运蛋白的NMR顺序参数的温度依赖性，目的是阐明相应的配体结合和自由形式之间的动力学差异。我们发现，在较高温度下稳定的蛋白质-配体相互作用对GlnBP大结构域的疏水核心的稳定性具有显著影响。此外，与对于较不特异的PBPs所发现的相反，铰链区在升高的温度下主链运动的降低支持GlnBP在溶液中可以采用无配体闭合构象的可能性在较高温度下减小的想法。我们的研究结果支持诱导拟合模型作为GlnBP的作用模式。此外，我们发现盐桥中涉及的残基的主链不一定如先前所建议的那样随着温度升高而变得更刚性[Vinther，J.M. et.等人（2011）J. Am.化学会，271-278]。我们的研究结果表明，要做到这一点，这些残基还必须与蛋白质的一个区域直接相互作用，该区域随着温度的升高而变得更加刚性。
Temperature dependence of dynamic parameters derived from nuclear magnetic resonance (NMR) relaxation data are related to conformational entropy of the system under study. This provides information such as macromolecules stability and thermodynamics of ligand binding. We studied the temperature dependence of NMR order parameter of Glutamine binding protein (GlnBP), a periplasmic binding protein (PBP) highly specific to L-glutamine associated with its ABC transporter, with the goal of elucidating the dynamical differences between the respective ligand bound and free forms. We found that the protein-ligand interaction, which is stabilized at higher temperature, has a striking effect on the stability of the hydrophobic core of the large domain of GlnBP. Moreover, in contrast to what was found for less specific PBPs the decreasing backbone motion of the hinge region at increasing temperature supports the idea that the likelihood that GlnBP can adopt a ligand free closed conformation in solution diminishes at higher temperatures. Our results support the induced-fit model as mode of action for GlnBP. In addition, we found that the backbones of residues involved in a salt bridge do not necessarily become more rigid as the temperature rises as it was previously suggested [Vinther, J.M. et. al. (2011) J. Am. Chem. Soc., 271–278]. Our results show that for this to happen, these residues have to also directly interact with a region of the protein that is becoming more rigid as the temperature increases.
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影响因子：
2.9
作者：
Bermejo, Guillermo A.;Strub, Marie-Paule;Ho, Chien;Tjandra, Nico
通讯作者：
Tjandra, Nico
影响因子：
2.9
作者：
CLORE, GM;DRISCOLL, PC;GRONENBORN, AM
通讯作者：
GRONENBORN, AM
影响因子：
5.6
作者：
Hsiao, CD;Sun, YJ;Wang, BC
通讯作者：
Wang, BC
影响因子：
15
作者：
LIPARI, G;SZABO, A
通讯作者：
SZABO, A
影响因子：
2.9
作者：
Mercier, P;Spyracopoulos, L;Sykes, BD
通讯作者：
Sykes, BD