Redox-Dependent Vibrational Energy Flow in Amicyanin Revealed by Molecular Dynamics Simulations
Serlin Nirmala Grazy Chinnappan1, Ramachandran Gnanasekaran1
1Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Chennai Campus, Chennai 600127, India.
The Journal of Physical Chemistry. B
|April 27, 2026
Summary
This study reveals that copper protein amicyanin uses a stable network of residues to transfer energy, regardless of its redox state. This conserved pathway ensures reliable communication between the copper center and the protein
Area of Science:
- Biophysics
- Biochemistry
- Molecular Dynamics
Background:
- Understanding intraprotein energy flow is key to biological electron transfer.
- Redox events significantly impact protein dynamics and function.
Purpose of the Study:
- Investigate redox-dependent vibrational energy redistribution in amicyanin.
- Elucidate energy transfer pathways and their modulation by copper oxidation state.
- Analyze interprotein coupling at the amicyanin-cytochrome c551i interface.
Main Methods:
- Atomistic molecular dynamics simulations.
- Time-correlation and cross-correlation analyses of residue-resolved energy fluctuations.
- Analysis of vibrational spectra, dynamical couplings, and energy transfer pathways.
Main Results:
- Vibrational energy propagates through a conserved network of residues in amicyanin.
- Energy transfer pathway efficiencies are similar in both Cu+ and Cu2+ states.
- Interfacial water at the amicyanin-cytochrome c551i complex mediates coherent interprotein coupling.
Conclusions:
- Amicyanin possesses a robust vibrational communication network conserved during redox cycling.
- This network enables reliable long-range dynamical coupling between redox chemistry and protein response.
- Interfacial water dynamics play a crucial role in interprotein energy transfer.
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