This series of antibacterial agents, known as the halogenated phenazines, are able to eradicate free-floating (planktonic) bacteria in addition to persistent, surface-attached bacterial biofilms against gram positive organisms such as methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE) and vancomycin-resistant Enterococcus faecium (VRE). Bacterial cells housed within a biofilm are metabolically dormant, persister cells that display high levels of tolerance towards conventional antibiotics and biocides. Bacterial biofilms occur in the majority of bacterial infections and accumulate on essentially all surface types, including medical implants and industrial pipes. Researchers at the University of Florida have discovered halogenated phenazine small molecules that are able to eradicate greater than 99.9 percent of biofilm cells through a mechanism that is non-toxic to mammalian cell lines, including red blood cells. In addition, select halogenated phenazine analogues have potent antibacterial activities against the slow-growing human pathogen Mycobacterium tuberculosis.
Clinical and non-clinical applications for eradicating biofilm-associated bacterial pathogens and surfaces colonized by persistent biofilms.
The halogenated phenazine scaffold is highly tunable, which has been demonstrated through the synthesis and evaluation of more than 80 synthetic analogues. Continued efforts are underway to further develop halogenated phenazines for numerous applications related to bacterial biofilm infections and disinfectants. These halogenated phenazines have demonstrated the most potent biofilm eradication activities reported in the literature against MRSA, MRSE and VRE biofilms. In addition to biofilms, select halogenated phenazine analogues demonstrate potent antibacterial activity against M. tuberculosis.