Aim: The aim of the study was to find out the role of auranofin as a promising broadspectrum
Methods: In vitro assays (Percentage growth retardation, Bacterial growth kinetics, Biofilm formation
assay) and In silico study (Molegro virtual docker (MVD) version 6.0 and Molecular operating
environment (MOE) version 2008.10 software).
Results: The in vitro assays have shown that auranofin has good antibacterial activity against Gram
positive and Gram negative bacterial strains. Further, auranofin has shown synergistic activity in
combination with ampicillin against S. aureus and B. subtilis whereas in combination with neomycin
has just shown additive effect against E. coli, P. aeruginosa and B. pumilus. In vivo results have
revealed that auranofin alone and in combination with standard drugs significantly decreased the
bioburden in the zebrafish infection model as compared to control. The molecular docking study
have shown good interaction of auranofin with penicillin-binding protein (2Y2M), topoisomerase
(3TTZ), UDP-3-O-[3-hydroxymyristoyl] N-acetylglucosaminedeacetylase (3UHM), cell adhesion
protein (4QRK), β-lactamase (5CTN) and arylsulphatase (1HDH) enzyme as that of reference ligand
which indicate the multimodal mechanism of action of auranofin. Finally, MTT assay has
shown the non-cytotoxic effect of auranofin.
Conclusion: In conclusion, auranofin in combination with existing antibiotics, could be developed
as a broad spectrum antibacterial agent; however, further studies are required to confirm its safety
and efficacy. This study provides the possibility of the use of auranofin apart from its established
therapeutic indication in combination with existing antibiotics to tackle the problem of resistance.