Fig. 1.

High-throughput screen for chemical inhibitors that displace a Pol III peptide from the β-clamp. (A) Titration of E. coli β into TAMN-labeled Pol III C-terminal 20-mer peptide is monitored by fluorescence anisotropy. (B) Inhibition of DNA replication by compounds identified in the peptide-displacement assay. The plot shows the percentage of inhibition of E. coli DNA Pol I Klenow versus β-dependent synthesis by Pol III* in the presence of 20 μM compound. (C) Chemicals (i.e., at 50 μM) that displace E. coli Pol III α-peptide from E. coli β were tested for ability to displace S. pyogenes Pol C peptide from S. pyogenes β.