DNA polymerase III subunit beta (Beta clamp)

The DNA polymerase III subunit beta, commonly known as the beta clamp, is a homodimeric protein that functions as a processivity factor for DNA replication in Escherichia coli (UniProt: P0A6H0). It forms a ring-shaped structure that encircles double-stranded DNA, tethering the DNA polymerase III core enzyme to the template and allowing for rapid and continuous nucleotide addition. Beyond replication, the beta clamp serves as a central scaffold for various proteins involved in DNA repair and recombination, coordinating these processes through a conserved hydrophobic pocket. Because of its essential role in bacterial survival and its structural divergence from the eukaryotic equivalent, Proliferating Cell Nuclear Antigen (PCNA), it is a promising target for the development of novel antibacterial agents. Inhibitors typically target the protein-protein interaction site to disrupt the assembly of the replisome, effectively halting bacterial proliferation (PMID: 26045431). This mechanism of action is distinct from traditional antibiotics, potentially providing a pathway to treat multi-drug resistant infections.

Other names

dnaNDNA sliding clampBeta subunit of DNA polymerase IIISliding clamp

Inhibition of protein-protein interactions (PPI) between the beta clamp and DNA polymerase III or other DNA-modifying enzymes by binding to the conserved hydrophobic pocket (PMID: 25104318).