A Novel Fluorescence-Based Screen for Inhibitors of the Initiation of DNA Replication in Bacteria

One of many strategies to overcome antibiotic resistance is the discovery of compounds targeting cellular processes, which have not yet been exploited.

Using various genetic tools, we constructed a novel high throughput, cellbased, fluorescence screen for inhibitors of chromosome replication initiation in bacteria.

The screen was validated by expression of an intra-cellular cyclic peptide interfering with the initiator protein DnaA and by over-expression of the negative initiation regulator SeqA. We also demonstrated that neither tetracycline nor ciprofloxacin triggers a false positive result. Finally, 400 extracts isolated mainly from filamentous actinomycetes were subjected to the screen.

We concluded that the presented screen is applicable for identifying putative inhibitors of DNA replication initiation in a high throughput setup.