Virtual Screening and Molecular Docking Analysis of Phytochemicals Derived from Woodfordia Fruticosa To Delineate Acinetobacter Baumannii OXA-23 Antagonists

Carbapenem resistant Acinetobacter baumannii, a leading contributor to nosocomial infections, is an alarming vulnerability to global population and modern healthcare systems. With expediated emergence of resistance, it has emanated as an obstinate opportunistic pathogen with high morbidity and mortality rates. Of several challenging and diverse resistance mechanisms possessed by the bacteria, OXA-23 carbapenemases are the cornerstone against carbapenems, the first line antibiotics against multidrug resistant strains. Given the paucity of available therapeutics, identification of novel antimicrobial agents is an urgent necessity to tackle this notorious pathogen. Phytochemicals because of their natural origin and low toxicities have gained immense popularity as enhancers or alternatives to existing antibiotics. This study intends to widen the scope of interventions against A. baumannii OXA-23. We performed molecular docking analysis using Autodock Vina to curate the phytochemical profile of an herbal plant Woodfordia fruticosa to predict their binding affinity towards OXA-23. Sixteen molecules exhibited higher binding affinities than the standard inhibitor used (Avibactam: -6.4 kcal/mol). The shortlisted molecules were further assessed for their drug likeliness properties via RO5 analysis and prediction of bioavailability and bioactivity scores. Maslinic acid and Oleanolic acid were the top lead molecules with binding energies as high as 9.4 kcal/mol and -9.0 kcal/mol respectively.