title: Chaperone-assisted excisive recombination, a solitary role for DnaJ (Hsp40) chaperone in lysogeny escape.
abstract: Temperate bacteriophage lytic development is intrinsically related to the stress response in particular at the DNA replication and virion maturation steps. Alternatively, temperate phages become lysogenic and integrate their genome into the host chromosome. Under stressful conditions, the prophage resumes a lytic development program, and the phage DNA is excised before being replicated. The KplE1 defective prophage of Escherichia coli K12 constitutes a model system because it is fully competent for integrative as well as excisive recombination and presents an atypical recombination module, which is conserved in various phage genomes. In this work, we identified the host-encoded stress-responsive molecular chaperone DnaJ (Hsp40) as an active participant in KplE1 prophage excision. We first show that the recombination directionality factor TorI of KplE1 specifically interacts with DnaJ. In addition, we found that DnaJ dramatically enhances both TorI binding to its DNA target and excisive recombination in vitro. Remarkably, such stimulatory effect by DnaJ was performed independently of its DnaK chaperone partner and did not require a functional DnaJ J-domain. Taken together, our results underline a novel and unsuspected functional interaction between the generic host stress-regulated chaperone and temperate bacteriophage lysogenic development.
authors: Laboratoire de Chimie Bactérienne CNRS UPR9043, Institut de Microbiologie de la Méditerranée, Aix-Marseille Université, 31 chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
authors: Stéphanie
authors: S
authors: Champ
authors: Tania M
authors: TM
authors: Puvirajesinghe
authors: Elsa
authors: E
authors: Perrody
authors: Rachid
authors: R
authors: Menouni
authors: Pierre
authors: P
authors: Genevaux
authors: Mireille
authors: M
authors: Ansaldi
mesh_terms: D004279:DNA, Viral / Q000235:genetics / Q000378:metabolism*; D048168:Escherichia coli K12 / Q000235:genetics / Q000378:metabolism* / Q000821:virology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D050956:HSP40 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D039002:Prophages / Q000502:physiology*; D017434:Protein Structure, Tertiary; D011995:Recombination, Genetic / Q000502:physiology*; D014775:Virus Activation / Q000502:physiology*
chemical_list: D004279:DNA, Viral; D029968:Escherichia coli Proteins; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; C488589:TorI protein, E coli; C063842:dnaK protein, E coli