Piperine analogues as dual inhibitors for antibacterial and antiarthritic properties through impact of ligands optimization, docking and water solvation

Abstract

The prevalence of bacterial diseases poses a significant challenge because of how they can develop resistance to antibiotics and evade the human immune system, highlighting the need for novel therapeutic approaches. Bacterial infection leads to the degradation of bone tissue and the development of arthritis. This study investigates the antibacterial and antirheumatic properties of piperine analogues. Computational analyses, including molecular docking quantum chemical studies and ADMET analysis, are performed to screen out potential inhibitory compounds. A library of 100 ligands is obtained from PubChem and subjected to virtual screening using various filters, including pharmacophore properties, molecular docking, and toxicity prediction, to identify potential candidates. Four compounds, P1-P4, are selected for further investigation using quantum chemical methods. These compounds are subjected to quantum chemical spectroscopic analysis, including UV–visible and IR spectra. The molecular geometries are fully optimized. HOMO and LUMO orbitals including their energies are calculated to estimate intermolecular charge transfer properties Molecular docking results revealed “compound P3 displayed the highest binding affinity to both proteins, with binding energies of 9.0 kcal/mol and 9.8 kcal/mol for FtsZ and Neutrophil collagenase proteins, respectively”. The analysis of 2D and 3D interactions between the selected compounds and both proteins reveals the formation of three important hydrogen bonds between ligand P3 and the FtsZ protein, as well as two hydrogen bonds between P3 and the Neutrophil collagenase protein. Additionally, ligand P4 forms three hydrogen bonds with the Neutrophil collagenase protein. The small energy gap of 3.85 eV between the HOMO and LUMO of the optimized molecule Neutrophil collagenase indicates that the compound is among the category of soft compounds and biologically more active. As new insights, for the first time, we performed a comparative analysis of the energies of the docked and optimized ligands that reveal the docked ligands always possess higher energies which might be considered as energy-penalty during the docking process. This energy penalty is found to be −24, −22, −26 and −32 kcal/mol for FtsZ and −169, −40, −35 and −39 Kcal/mol for Neutrophil collagenase P1-P4, respectively. The orbital energy gap further decreases in solvation with water and increases its chemical reactivity. Under the solvation effect of water as solvent, the quantum computational results indicated enhanced molecular solubility and stability, which are critical factors for bioavailability. The researchers suggested that the combination of increased reactivity and better solubility ensures that the drug performs more effectively in biological environments, making it a more potent inhibitor for bacterial infections and arthritis. The molecular geometries including bond lengths and bond angles of all studied compounds were also influenced in a solvent environment.