Computational analysis of the activity of pongachalcone I against highly resistant bacteria Pseudomonas putida

TtgR is a multi­drug binding protein in the gram negative bacteria Pseudomonas putida (DOT­T1E strain) and regulates one of the key mechanisms of its antibiotic resistance by active extrusion of toxic compounds through the membrane­bound efflux pumps. The paper reports the molecular docking studies of Pongachalcone I, a natural pyranochalcone and reported potent inhibitor of the bacteria, on the transcriptional regulator (TtgR) enzyme (PDB Code: 2UXI) which is a key efflux pump TtgABC operon repressor. Although the bacterium is capable to expel antibiotics like Chloramphenicol, Tetracycline and Naringenin, yet Pongachalcone I has potent activity against it. The work unveils the key roles played by the residues ASN 110 and CYS 137 in the active site of the enzyme, which would be highly beneficial in providing insight into the molecular mechanism of multiple drug recognition and in designing drugs for antibiotic resistance bacteria.