Density functional study of Cu(2+)-phenylalanine complex under micro-solvation environment

Area of Science:

• Computational Chemistry
• Biophysical Chemistry
• Materials Science

Background:

• Understanding metal-ligand interactions is crucial in biochemistry and materials science.
• The behavior of amino acid-metal complexes in solution influences biological processes and catalytic activity.

Purpose of the Study:

• To investigate the atomistic structures of phenylalanine-copper (II) ([Phe-Cu](2+)) complexes.
• To explore the micro-solvation processes and structural dynamics of these complexes.

Main Methods:

• Density functional theory (DFT) calculations.
• Structural relaxations and Car-Parrinello Molecular Dynamics (CPMD) simulations.
• B3LYP/6-311++G** model for gas-phase optimization.

Main Results:

• Phenylalanine transitions from neutral to zwitterionic form with increasing hydration (n≥2).
• Copper (II) coordination in [Phe-Cu](2+) complexes does not exceed four, involving water and carboxylate oxygen.
• A stabilizing structural motif, (N)H···O(3)···H2O-Cu(2+), was identified.

Conclusions:

• The study elucidates the structural preferences and solvation behavior of [Phe-Cu](2+) complexes.
• Identified key interactions and coordination numbers provide insights into the stability and dynamics of these systems.
• The findings contribute to understanding metal-amino acid complexation in aqueous environments.