Abstract
Recently, studies on the interactions between ovalbumin (OVA) and polyphenols have received a great deal of interest. This study explored the conformational changes and the interaction mechanism of the binding between OVA and chlorogenic acid (CGA) isomers such as 3,4-dicaffeoylquinic acids (3,4-diCQA), 4,5-dicaffeoylquinic acids (4,5-diCQA), and 3,5-dicaffeoylquinic acids (3,5-diCQA) using multispectroscopic and in silico analyses. The emission spectra show that the diCQAs caused strong quenching of OVA fluorescence under different temperatures through a static quenching mechanism with hydrogen bond (H-bond) and van der Waals (vdW) interactions. The values of binding constants (OVA-3,4-diCQA = 6.123 × 105, OVA-3,5-diCQA = 2.485 × 105, OVA-4,5-diCQA = 4.698 × 105dm3mol-1at 298 K) suggested that diCQAs had a strong binding affinity toward OVA, among which OVA-3,4-diCQA exhibits higher binding constant. The results of UV-vis absorption and synchronous fluorescence indicated that the binding of all three diCQAs to OVA induced conformational and micro-environmental changes in the protein. The findings of molecular modeling further validate the significant role of vdW force and H-bond interactions in ensuring the stable binding of OVA-diCQA complexes. Temperature-dependent molecular dynamics simulation studies allow estimation of the individual components that contribute to the total bound free energy value, which allows evaluation of the nature of the interactions involved. This research can provide information for future investigations on food proteins' physicochemical stability and CGA bioavailability in vitro or in vivo.
| Original language | English |
|---|---|
| Pages (from-to) | 6133-6147 |
| Number of pages | 15 |
| Journal | Journal of Chemical Information and Modeling |
| Volume | 62 |
| Issue number | 23 |
| DOIs | |
| Publication status | Published - 12 Dec 2022 |
| MoE publication type | A1 Journal article-refereed |
Funding
This study was supported by the Jiangsu Specially-Appointed Professor Program (19TPJS-002) and Senior Talent Startup Fund of Jiangsu University (4111360002) to X.C. P.M. acknowledges the China Postdoctoral Science Foundation and Jiangsu University for the financial Support. Dr. M. Ilanchelian (Bharathiar University) is gratefully acknowledged for allowing us to record the required instrumentation facility and providing the laboratory support. Parthiban, M. gratefully acknowledges the use of the bioinformatics infrastructure facility supported by Biocenter Finland, grants from the Joe, Pentti, and Tor Borg Memorial Fund in 2021, the Sigrid Juselius Foundation, and the CSC-IT Center for Science (project: 2000461) for the computational facility; Dr. Jukka Lehtonen for the IT support and Prof. Mark Johnson (SBL) and Prof. Outi Salo-Ahen (Pharmacy) Åbo Akademi University for providing the laboratory support.