Ligand-Based Drug Design of Novel Antimicrobials against Staphylococcus aureus by Targeting Bacterial Transcription

Area of Science:

• Microbiology
• Drug Discovery
• Computational Chemistry

Background:

• Staphylococcus aureus poses a significant threat due to rising antimicrobial resistance, leading to MRSA and MDRSA strains.
• Bacterial transcription is a promising, yet underutilized, target for novel antimicrobial development.
• Nusbiarylins, a previously reported antimicrobial class, inhibit transcription by disrupting NusB-NusE protein-protein interactions.

Purpose of the Study:

• To develop a ligand-based computational workflow for identifying novel antimicrobials targeting Staphylococcus aureus.
• To screen a chemical database for compounds that inhibit bacterial transcription via NusB-NusE interaction.

Main Methods:

• Development of a ligand-based workflow incorporating pharmacophore modeling, 3D QSAR, AutoQSAR, and ADME/T calculations.
• Virtual screening of the ChemDiv PPI database using the developed models.
• Molecular docking studies to assess binding affinity to the NusB protein.

Main Results:

• Identification of four potential antimicrobial compounds: J098-0498, 1067-0401, M013-0558, and F186-026.
• Predicted pMIC values for the identified compounds ranged from 3.8 to 4.2.
• Docking studies revealed strong binding of these compounds to NusB, with binding free energies from -58 to -66 kcal/mol.

Conclusions:

• The developed ligand-based workflow is effective in identifying novel antimicrobial candidates against Staphylococcus aureus.
• The identified compounds represent promising leads for developing new treatments against antibiotic-resistant bacterial infections.
• Targeting bacterial transcription, specifically the NusB-NusE interaction, offers a viable strategy for combating superbugs.