Quantum-Mechanical Prediction of Gas Phase Biomolecular Secondary Structure

Abstract

The accurate computational prediction of peptide / protein behaviour is among the most competitive research areas today, but fully QM predictions (here: van der Waals corrected density functional theory) for such systems are still hampered by the computational demands for the necessary molecular dynamics timescales. DEISA will allow us to advance these limits significantly, by predicting conformational equilibria and ensembles of two benchmark peptides, Ac-Ala₁₉-Lys-H⁺ and (Ac-Lys-Ala₁₉-H⁺)₂ (220 and 440 atoms, respectively). Key parts of the results can be directly compared to accurate gas-phase experimental data (vibrational spectroscopy), and will provide a key check and corroboration of the current ideas of secondary structure formation and its driving force in such molecules.