Multi-spectroscopic and molecular modeling investigation of the interactions between prantschimgin and matrix metalloproteinase 9 (MMP9).

The binding of prantschimgin (PRAN) to matrix metalloproteinase 9 (MMP9) was investigated using multiple techniques. Fluorescence spectroscopy showed that PRAN could quench the MMP9 fluorescence spectra. Changes in the UV/vis and Fourier transform infrared (FTIR) spectra were observed upon ligand binding, along with a significant degree of tryptophan fluorescence quenching on complex formation. The interaction of PRAN with MMP9 has also been studied using molecular docking and molecular dynamics (MD) simulation. The binding models demonstrated aspects of PRAN's conformation, active site interaction, important amino acids and hydrogen bonding. Computational mapping of the possible binding site of PRAN revealed that the ligand is bound in a large hydrophobic cavity of MMP9. The MD simulation results suggested that this ligand can interact with the protein, with little affecting the secondary structure. The results not only lead to a better understanding of interactions between PRAN and MMP9, but also provide useful data about the influence of PRAN on the structural conformation. The data provided in this study will be useful for designing a new agonist of MMP9 with the desired activity.