title: Exchange between Escherichia coli polymerases II and III on a processivity clamp.
abstract: Escherichia coli has three DNA polymerases implicated in the bypass of DNA damage, a process called translesion synthesis (TLS) that alleviates replication stalling. Although these polymerases are specialized for different DNA lesions, it is unclear if they interact differently with the replication machinery. Of the three, DNA polymerase (Pol) II remains the most enigmatic. Here we report a stable ternary complex of Pol II, the replicative polymerase Pol III core complex and the dimeric processivity clamp, β. Single-molecule experiments reveal that the interactions of Pol II and Pol III with β allow for rapid exchange during DNA synthesis. As with another TLS polymerase, Pol IV, increasing concentrations of Pol II displace the Pol III core during DNA synthesis in a minimal reconstitution of primer extension. However, in contrast to Pol IV, Pol II is inefficient at disrupting rolling-circle synthesis by the fully reconstituted Pol III replisome. Together, these data suggest a β-mediated mechanism of exchange between Pol II and Pol III that occurs outside the replication fork.
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: James E
authors.identifier: http://orcid.org/0000-0003-3767-9822
authors.initials: JE
authors.lastname: Kath
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Seungwoo
authors.initials: S
authors.lastname: Chang
authors.affiliation: Department of Biochemistry, University at Buffalo, State University of New York, Buffalo, NY 14214, USA Witebsky Center for Microbial Pathogenesis and Immunology, University at Buffalo, State University of New York, Buffalo, NY 14214, USA.
authors.forename: Michelle K
authors.initials: MK
authors.lastname: Scotland
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Johannes H
authors.initials: JH
authors.lastname: Wilbertz
authors.affiliation: Centre for Medical & Molecular Bioscience, Illawarra Health & Medical Research Institute and University of Wollongong, New South Wales 2522, Australia.
authors.forename: Slobodan
authors.initials: S
authors.lastname: Jergic
authors.affiliation: Centre for Medical & Molecular Bioscience, Illawarra Health & Medical Research Institute and University of Wollongong, New South Wales 2522, Australia.
authors.forename: Nicholas E
authors.initials: NE
authors.lastname: Dixon
authors.affiliation: Department of Biochemistry, University at Buffalo, State University of New York, Buffalo, NY 14214, USA Witebsky Center for Microbial Pathogenesis and Immunology, University at Buffalo, State University of New York, Buffalo, NY 14214, USA Genetics, Genomics and Bioinformatics Program, University at Buffalo, State University of New York, Buffalo, NY 14214, USA.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Sutton
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA joseph_loparo@hms.harvard.edu.
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Loparo
mesh_terms: D004247:DNA / Q000096:biosynthesis* / Q000235:genetics; D004249:DNA Damage / Q000235:genetics; D004257:DNA Polymerase II / Q000737:chemistry / Q000235:genetics*; D004258:DNA Polymerase III / Q000737:chemistry / Q000235:genetics*; D019951:DNA Polymerase beta / Q000737:chemistry / Q000235:genetics*; D004260:DNA Repair / Q000235:genetics; D004261:DNA Replication / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D046912:Multiprotein Complexes / Q000737:chemistry / Q000235:genetics; D017434:Protein Structure, Tertiary
chemical_list: D046912:Multiprotein Complexes; D004247:DNA; D004257:DNA Polymerase II; D004258:DNA Polymerase III; D019951:DNA Polymerase beta