COMPUTATIONAL SCREENING OF PHYTOCHEMICALS FROM NIGERIAN MEDICINAL PLANTS AS POTENTIAL INHIBITORS OF STAPHYLOCOCCUS AUREUS DNA GYRASE B

The increasing burden of antimicrobial resistance (AMR), particularly in Staphylococcus aureus, underscores the need to identify novel chemical scaffolds for targeting essential bacterial processes. DNA gyrase B (GyrB), the ATPase subunit of bacterial DNA gyrase, represents a promising antibacterial target. Antimicrobial resistance in Staphylococcus aureus presents a continuing challenge to effective antibacterial treatment. This study computationally screened phytochemicals associated with Nigerian medicinal plants to identify potential inhibitors of S. aureus DNA gyrase B (GyrB). Candidate compounds were selected from published ethnobotanical and phytochemical literature, and their chemical structures were prepared for molecular docking against GyrB (PDB ID: 4URO) using AutoDock Vina through PyRx. Novobiocin was used as the reference inhibitor. Predicted protein–ligand interactions and absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties were subsequently examined. Tiliacorine exhibited the most favourable docking score (−9.5 kcal/mol), followed by ellagic acid (−9.2 kcal/mol), bidebiline (−9.0 kcal/mol), and diospyrin (−8.8 kcal/mol), compared with −8.6 kcal/mol for novobiocin. Interaction analysis indicated recurring predicted contacts involving Asp81 and Gly85, with additional interactions reported for tiliacorine involving Arg84 and Arg144. ADMET predictions suggested comparatively favourable drug-likeness characteristics for diospyrin and ellagic acid, although potential pharmacokinetic and toxicity limitations were identified. Tiliacorine and bidebiline also exhibited predicted safety concerns. These findings identify selected phytochemicals as candidates for further investigation but do not establish GyrB inhibition or antibacterial efficacy. Experimental enzyme-inhibition assays, antibacterial susceptibility testing, and safety evaluation are required to validate their therapeutic potential