Exploration of Alpha-Curcumene and Curdione from Turmeric (Curcuma longa L.) to MurB Enzyme as Antibacterial through Molecular Docking Analysis

Original/Research Article

Abstract

Antimicrobial resistance (AMR) has emerged as a critical global health threat, necessitating the discovery of antibacterial agents with novel mechanisms of action. MurB, an essential enzyme in bacterial cell wall biosynthesis, represents an attractive target due to its absence in humans.  This study aimed to evaluate the in silico antibacterial potential of α-curcumene and curdione, two bioactive constituents of turmeric  essential oil, as inhibitors of the MurB enzyme.  The three-dimensional structure of MurB was retrieved from the Protein Data Bank. The chemical structures of α-curcumene and curdione were obtained from the PubChem database. Molecular docking was performed using AutoDock Vina, with naphthyl tetronic acid (co-crystallized ligand) as a positive control. Binding affinities and interaction profiles were analyzed using PyMOL and Discovery Studio Visualizer.  The native ligand exhibited a binding energy of -8.6 kcal/mol. Curdione demonstrated a binding energy of -6.7 kcal/mol, while α-curcumene showed -5.9 kcal/mol. Both compounds docked within the catalytic pocket, interacting with key residues Glu325, Ser229, and Arg159. Curdione exhibited superior binding affinity compared to α-curcumene.  Although both compounds showed weaker binding affinity than the native ligand, their ability to occupy the MurB active site suggests they are promising lead scaffolds for antibacterial drug development. Further in vitro and in vivo studies are warranted to validate their biological activity.