title: AbpA and AbpB provide anti-phage activity in Escherichia coli.
abstract: Bacteria have a variety of resistance mechanisms for surviving bacteriophage infections. Here, we describe a novel anti-phage mechanism in Escherichia coli. Cells harboring a plasmid with the genes abpA and abpB, formerly yfjL and yfjK, blocked the propagation of bacteriophages belonging to three families: T4, T2, T7 and λ phages. Both genes were necessary for the inhibition of phage propagation, and deletion of either chromosomal gene resulted in a 20% increase of progeny compared to wild-type cells. Neither overexpression nor deficiency of AbpA and AbpB had any apparent effect on E. coli growth. We isolated seven suppressor mutants of T4 phage that grew weakly on cells overexpressing AbpA and AbpB, and found that their mutations were all located in gene 41, which encodes a replicative DNA helicase that is essential for DNA replication. Furthermore, we demonstrated that AbpA and AbpB inhibited DNA replication and late gene expression of T4 phage. Similarly, DNA replication of T7 and λ phages was also inhibited by AbpA and AbpB. These results strongly suggest that E. coli AbpA and AbpB target DNA replication of phages to block their propagation.
authors.affiliation: Department of Biological Sciences, Graduate School of Science, Osaka University.
authors.forename: Ryota
authors.initials: R
authors.lastname: Yasui
authors.forename: Ayaka
authors.initials: A
authors.lastname: Washizaki
authors.forename: Yuko
authors.initials: Y
authors.lastname: Furihata
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Yonesaki
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Otsuka
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D003090:Coliphages / Q000502:physiology*; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism; D004261:DNA Replication; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics* / Q000821:virology; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D010957:Plasmids / Q000235:genetics; D014779:Virus Replication
chemical_list: D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial; D004265:DNA Helicases