Conformational Features of ACE-Inhibitory Valine-Isoleucine-Proline Tripeptide in Aqueous Medium According to Molecular Dynamic Simulations and 2D-NMR Spectroscopy

Molecular dynamic simulations and 2D-NMR spectroscopy were performed to study the conformations and hydrogen-bonding interactions of ACE-inhibitory valine–isoleucine–proline (VIP) tripeptide in aqueous solution. Intra-molecular distance, solvent-accessible surface, radius of gyration and root-mean-square deviations were used to describe the properties of the VIP in aqueous solution. MD results showed that the VIP molecule is highly flexible in water and the conformations can change from extended state to folded states. The VIP molecule exists in the extended state most of the time, which is in good agreement with the 2D-NMR spectra. Molecular dynamic simulations revealed that the ACE-inhibitory tri-peptide VIP is highly flexible in aqueous solution. The conformations can change from extended states to folded states. At most of the time, the VIP molecule exists in the extended state. Findings in simulations have been confirmed by 2D-NOESY spectrum.