Study of non-covalent complexation between catechin derivatives and peptides by electrospray ionization mass spectrometry.
The recent development of electrospray ionization mass spectrometry (ESI-MS) has allowed its use to study molecular interactions driven by non-covalent forces. ESI-MS has been used to detect non-covalent complexes between proteins and metals, ligands and peptides and interactions involving DNA, RNA, oligonucleotides and drugs. Surprisingly, the study of the interaction between polyphenolic molecules and peptides/proteins is still an area where ESI-MS has not benefited. With regard to the important influence of these interactions in the biological and food domains, ESI-MS was applied to the detection and the characterization of soluble polyphenol-peptide complexes formed in model solution. The ability to observe and monitor the weak interactions involved in such macromolecular complexation phenomena was demonstrated for monomeric and dimeric flavonoid molecules (catechin-derived compounds) largely encountered in plants and plant derived products. Intact non-covalent polyphenol-peptide complexes were observed by ESI-MS using different experimental conditions. Utilizing mild ESI interface conditions allowed the detection of 1 : 1 polyphenol-peptide complexes in all tested solutions and 2 : 1 complexes for the dimers and galloylated polyphenols (flavanols). These results show that there is a preferential interaction between polymerized and/or galloylated polyphenols and peptide compared with that between monomeric polyphenols and peptides. Thus, ESI-MS shows potential for the study of small polyphenolic molecule-peptide interactions and determination of stoichiometry.
Sarni-Manchado
Pascale
P
Unité Mixte de Recherche Sciences pour l'Oenologie, INRA, 2 place Viala, 34060 Montpellier, France. sarni@ensam.inra.fr
Cheynier
Véronique
V
D000595:Amino Acid Sequence; D002392:Catechin / Q000031:analogs & derivatives* / Q000737:chemistry*; D019281:Dimerization; D005504:Food Analysis; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D055232:Proline-Rich Protein Domains; D012996:Solutions; D021241:Spectrometry, Mass, Electrospray Ionization
D046911:Macromolecular Substances; D010446:Peptide Fragments; D010455:Peptides; D012996:Solutions; C417940:gallocatechin gallate; D002392:Catechin; C062669:epicatechin gallate; C045651:epigallocatechin gallate; C057580:gallocatechol