Premium
Binding of Lanthanide Complexes to Histidine‐Containing Peptides Probed by Raman Optical Activity Spectroscopy
Author(s) -
Brichtová Eva,
Hudecová Jana,
Vršková Nikola,
Šebestík Jaroslav,
Bouř Petr,
Wu Tao
Publication year - 2018
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201800840
Subject(s) - histidine , lanthanide , peptide , chemistry , biomolecule , luminescence , residue (chemistry) , raman spectroscopy , crystallography , raman optical activity , stereochemistry , amino acid , molecule , biochemistry , materials science , organic chemistry , ion , optics , physics , optoelectronics
Lanthanide complexes are used as convenient spectroscopic probes for many biomolecules. Their binding to proteins is believed to be enhanced by the presence of histidine, but the strength of the interaction significantly varies across different systems. To understand the role of peptide length and sequence, short histidine‐containing peptides have been synthesized (His‐Gly, His‐Gly‐Gly, His‐Gly‐Gly‐Gly, Gly‐His, Gly‐His‐Gly, His‐His, and Gly‐Gly‐His) and circularly polarized luminescence (CPL) induced at the [Eu(dpa) 3 ] 3− complex has been measured by means of a Raman optical activity (ROA) spectrometer. The obtained data indicate relatively weak binding of the histidine residue to the complex, with a strong participation of other parts of the peptide. Longer peptides, low pH, and a histidine residue close to the N ‐peptide terminus favor the binding. The binding strengths are approximately proportional to the CPL intensity and roughly correlate with predictions based on molecular dynamics (MD) simulations. The specificity of lanthanide binding to the peptide structure and its intense luminescence and high optical activity make the ROA/CPL technique suitable for probing secondary and tertiary structures of peptides and proteins.