Identification of Ribonuclease Inhibitors for the Control of Pathogenic Bacteria

Bacteria are known to be constantly adapting to become resistant to antibiotics. Currently, efficient antibacterial compounds are still available; however, it is only a matter of time until these compounds also become inefficient. Ribonucleases are the enzymes responsible for the maturation and degradation of RNA molecules, and many of them are essential for microbial survival. Members of the PNPase and RNase II families of exoribonucleases have been implicated in virulence in many pathogens and, as such, are valid targets for the development of new antibacterials. In this paper, we describe the use of virtual high-throughput screening (vHTS) to identify chemical compounds predicted to bind to the active sites within the known structures of RNase II and PNPase from Escherichia coli. The subsequent in vitro screening identified compounds that inhibited the activity of these exoribonucleases, with some also affecting cell viability, thereby providing proof of principle for utilizing the known structures of these enzymes in the pursuit of new antibacterials.