DNA polymerase III subunit beta (DnaN) (DnaN)

Pseudomonas aeruginosa DnaN, also known as the beta-clamp or DNA polymerase III subunit beta, is a critical component of the bacterial replisome. It functions as a ring-shaped processivity factor that encircles DNA, tethering the DNA polymerase III catalytic core to the template and allowing for rapid, continuous synthesis of the bacterial genome. Beyond its role in replication, DnaN serves as a central scaffold for various DNA repair enzymes and the clamp-loader complex. Its essential nature for bacterial viability and its significant structural divergence from the human equivalent, PCNA, make it a high-priority target for novel antimicrobial development. While no drugs are currently approved for clinical use against this specific Pseudomonas target, investigational compounds such as griselimycin and its derivatives have shown potent activity by binding to the hydrophobic pocket on the clamp surface, thereby halting DNA replication and causing bacterial cell death.

Other names

Beta-clampDNA sliding clampDNA polymerase III beta subunitSliding clamp proteinDnaN protein

Inhibits DNA replication by binding to the DnaN sliding clamp and competitively blocking its interaction with the replicative DNA polymerase (Pol III alpha subunit) and other repair/clamp-loader proteins at the C-terminal binding pocket.