Journal articles
Sampling the protonation states: the pH-dependent UV absorption spectrum of a polypeptide dyad
Abstract : When a chromophore interacts with several titratable molecular sites, the modeling of its photo-physical properties requires to take into account all their possible protonation states. We have developed a multi-scale protocol, based on constant-pH molecular dynamics simulations coupled to QM/MM excitation energy calculations, aimed at sampling both the phase space and protona-tion state space of a short polypeptide featuring a tyrosine-tryptophan dyad interacting with two aspartic acid residues. We show that such a protocol is accurate enough to help in the interpretation of the experimental tyrosine UV absorption spectrum at both acidic and basic pH. Moreover, it is confirmed that radical tryptophan probably contributes to the peptide spectrum, thanks to a UV-induced electron transfer from tyrosine to tryptophan, ultimately shedding light on the complex pH-dependent behavior of the peptide spectrum.
Cited literature [45 references]
https://hal-amu.archives-ouvertes.fr/hal-02053144
Contributor : Nicolas Ferré <>
Submitted on : Friday, March 1, 2019 - 9:49:00 AM
Last modification on : Wednesday, December 9, 2020 - 3:13:45 AM
Long-term archiving on: : Thursday, May 30, 2019 - 12:45:18 PM
Contributor : Nicolas Ferré <>
Submitted on : Friday, March 1, 2019 - 9:49:00 AM
Last modification on : Wednesday, December 9, 2020 - 3:13:45 AM
Long-term archiving on: : Thursday, May 30, 2019 - 12:45:18 PM
File
peptideM_v3.pdf
Publication funded by an institution
Licence
Distributed under a Creative Commons Attribution 4.0 International License