title: Functional characterization of the repA replication gene of linear plasmid prophage N15.
abstract: The prophage of coliphage N15 is not integrated into the chromosome, but exists as a linear plasmid molecule with covalently closed ends. The only phage gene required for replication of circular N15 miniplasmids is repA (gene 37). Here we show that RepA-driven replication of the N15-based circular and linear miniplasmids is independent of host DnaB helicase protein, but requires the host DnaG primase. Replication of phage N15 DNA during lytic growth following infection does not depend on either DnaG or DnaB, but DnaG is required for lytic development after induction of the N15 lysogen. Finally, protein sequence analysis and replication data using different mutant strains suggest that RepA protein combines helicase and primase functions.
authors.affiliation: Centre "Bioengineering", Russian Academy of Sciences, Prosp. 60-let Oktiabria, bld. 7-1, Moscow 117312, Russia.
authors.forename: Andrey V
authors.initials: AV
authors.lastname: Mardanov
authors.forename: Nikolai V
authors.initials: NV
authors.lastname: Ravin
mesh_terms: D000251:Adenosine Triphosphatases / Q000502:physiology; D001483:Base Sequence; D003090:Coliphages / Q000235:genetics* / Q000254:growth & development; D004265:DNA Helicases / Q000235:genetics / Q000502:physiology; D019915:DNA Primase / Q000235:genetics / Q000502:physiology; D004279:DNA, Viral / Q000378:metabolism; D053488:DnaB Helicases; D004706:Endodeoxyribonucleases / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics / Q000502:physiology / Q000821:virology*; D029968:Escherichia coli Proteins / Q000502:physiology; D005090:Exodeoxyribonucleases / Q000502:physiology; D005814:Genes, Viral; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids / Q000235:genetics; D039002:Prophages / Q000235:genetics* / Q000254:growth & development; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication / Q000235:genetics*
chemical_list: D004279:DNA, Viral; D029968:Escherichia coli Proteins; D014764:Viral Proteins; D019915:DNA Primase; D004706:Endodeoxyribonucleases; D005090:Exodeoxyribonucleases; C121791:dnaG protein, E coli; D000251:Adenosine Triphosphatases; C506730:dnaB protein, E coli; D004265:DNA Helicases; D053488:DnaB Helicases