2013年1月
Principal component analysis of chemical shift perturbation data of a multiple-ligand-binding system for elucidation of respective binding mechanism
PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS
- ,
- ,
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- 巻
- 81
- 号
- 1
- 開始ページ
- 107
- 終了ページ
- 118
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1002/prot.24166
- 出版者・発行元
- WILEY
Chemical shift perturbations (CSPs) in NMR spectra provide useful information about the interaction of a protein with its ligands. However, in a multiple-ligand-binding system, determining quantitative parameters such as a dissociation constant (Kd) is difficult. Here, we used a method we named CS-PCA, a principal component analysis (PCA) of chemical shift (CS) data, to analyze the interaction between bovine beta-lactoglobulin (beta LG) and 1-anilinonaphthalene-8-sulfonate (ANS), which is a multiple-ligand-binding system. The CSP on the binding of ANS involved contributions from two distinct binding sites. PCA of the titration data successfully separated the CSP pattern into contributions from each site. Docking simulations based on the separated CSP patterns provided the structures of beta LGANS complexes for each binding site. In addition, we determined the Kd values as 3.42 x 10-4M2 and 2.51 x 10-3M for Sites 1 and 2, respectively. In contrast, it was difficult to obtain reliable Kd values for respective sites from the isothermal titration calorimetry experiments. Two ANS molecules were found to bind at Site 1 simultaneously, suggesting that the binding occurs cooperatively with a partial unfolding of the beta LG structure. On the other hand, the binding of ANS to Site 2 was a simple attachment without a significant conformational change. From the present results, CS-PCA was confirmed to provide not only the positions and the Kd values of binding sites but also information about the binding mechanism. Thus, it is anticipated to be a general method to investigate proteinligand interactions. Proteins 2013. (c) 2012 Wiley Periodicals, Inc.
- リンク情報
- ID情報
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- DOI : 10.1002/prot.24166
- ISSN : 0887-3585
- eISSN : 1097-0134
- PubMed ID : 22927212
- Web of Science ID : WOS:000312551700008