Combining molecular docking and molecular dynamics studies for modelling Staphylococcus aureus MurD inhibitory...

Area of Science:

• Biochemistry
• Molecular Biology
• Drug Discovery

Background:

• The bacterial MurD enzyme is crucial for peptidoglycan synthesis, making it a vital target for novel antibacterial agents.
• Staphylococcus aureus MurD is essential for cell wall formation in both Gram-positive and Gram-negative bacteria.

Purpose of the Study:

• To investigate the inhibition potential of a 2-thioxothiazolidin-4-one based inhibitor against Staphylococcus aureus MurD.
• To elucidate the molecular interactions and stability of inhibitor-protein complexes using computational methods.

Main Methods:

• Homology modeling was used to generate the 3D structure of the S. aureus MurD catalytic pocket.
• Extra-precision molecular docking, MM-GBSA binding free energy calculations, and molecular dynamics (MD) simulations (40 ns and 20 ns) were performed.
• Key amino acid residues (Lys19, Gly147, Tyr148, Lys328, Thr330, Phe431) involved in inhibitor binding were identified.

Main Results:

• Molecular docking revealed specific residues crucial for stabilizing the inhibitor-protein complex.
• Binding free energy calculations indicated that electrostatic solvation and van der Waals forces are major contributors to inhibitor binding.
• Molecular dynamics simulations confirmed the stable conformation of the inhibitor-S. aureus MurD complex.

Conclusions:

• The study provides insights into the binding mechanism of 2-thioxothiazolidin-4-one based inhibitors with S. aureus MurD.
• Computational approaches successfully validated the stability of designed inhibitors.
• These findings can guide the rational design of potent S. aureus MurD inhibitors for developing new antibacterial therapies.