This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
2pnh
From Proteopedia
|
Escherichia coli PriB E39A variant
Overview
Collapsed DNA replication forks must be reactivated through, origin-independent reloading of the replication machinery (replisome) to, ensure complete duplication of cellular genomes. In E. coli, the, PriA-dependent pathway is the major replication restart mechanism and, requires primosome proteins PriA, PriB, and DnaT for replisome reloading., However, the molecular mechanisms that regulate origin-independent, replisome loading are not fully understood. Here, we demonstrate that, assembly of primosome protein complexes represents a key regulatory, mechanism, as inherently weak PriA-PriB and PriB-DnaT interactions are, strongly stimulated by single-stranded DNA. Furthermore, the binding site, on PriB for single-stranded DNA partially overlaps the binding sites for, PriA and DnaT, suggesting a dynamic primosome assembly process in which, single-stranded DNA is handed off from one primosome protein to another as, a repaired replication fork is reactivated. This model helps explain how, origin-independent initiation of DNA replication is restricted to repaired, replication forks, preventing overreplication of the genome.
About this Structure
2PNH is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
A hand-off mechanism for primosome assembly in replication restart., Lopper M, Boonsombat R, Sandler SJ, Keck JL, Mol Cell. 2007 Jun 22;26(6):781-93. PMID:17588514
Page seeded by OCA on Wed Nov 21 13:36:18 2007
