title: Development of giant bacteriophage ϕKZ is independent of the host transcription apparatus.
abstract: Pseudomonas aeruginosa bacteriophage ϕKZ is the type representative of the giant phage genus, which is characterized by unusually large virions and genomes. By unraveling the transcriptional map of the ∼ 280-kb ϕKZ genome to single-nucleotide resolution, we combine 369 ϕKZ genes into 134 operons. Early transcription is initiated from highly conserved AT-rich promoters distributed across the ϕKZ genome and located on the same strand of the genome. Early transcription does not require phage or host protein synthesis. Transcription of middle and late genes is dependent on protein synthesis and mediated by poorly conserved middle and late promoters. Unique to ϕKZ is its ability to complete its infection in the absence of bacterial RNA polymerase (RNAP) enzyme activity. We propose that transcription of the ϕKZ genome is performed by the consecutive action of two ϕKZ-encoded, noncanonical multisubunit RNAPs, one of which is packed within the virion, another being the product of early genes. This unique, rifampin-resistant transcriptional machinery is conserved within the diverse giant phage genus.
  
  
  OBJECTIVE
  The data presented in this paper offer, for the first time, insight into the complex transcriptional scheme of giant bacteriophages. We show that Pseudomonas aeruginosa giant phage ϕKZ is able to infect and lyse its host cell and produce phage progeny in the absence of functional bacterial transcriptional machinery. This unique property can be attributed to two phage-encoded putative RNAP enzymes, which contain very distant homologues of bacterial β and β'-like RNAP subunits.
authors: Division of Gene Technology, KU Leuven, Heverlee, Belgium.
authors: Pieter-Jan
authors: PJ
authors: Ceyssens
authors: Waksman Institute of Microbiology, Rutgers University, New Jersey, USA.
authors: Leonid
authors: L
authors: Minakhin
authors: Division of Gene Technology, KU Leuven, Heverlee, Belgium.
authors: An
authors: A
authors: Van den Bossche
authors: St. Petersburg State Polytechnical University, St. Petersburg, Russia.
authors: Maria
authors: M
authors: Yakunina
authors: St. Petersburg State Polytechnical University, St. Petersburg, Russia Institutes of Molecular Genetics and Gene Biology, Russian Academy of Sciences, Moscow, Russia Skolkovo Institute of Science and Technology, Skolkovo, Russia.
authors: Evgeny
authors: E
authors: Klimuk
authors: Division of Gene Technology, KU Leuven, Heverlee, Belgium.
authors: Bob
authors: B
authors: Blasdel
authors: Division of Gene Technology, KU Leuven, Heverlee, Belgium.
authors: Jeroen
authors: J
authors: De Smet
authors: Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium.
authors: Jean-Paul
authors: JP
authors: Noben
authors: Max F. Perutz Laboratories, University of Vienna, Vienna, Austria.
authors: Udo
authors: U
authors: Bläsi
authors: Waksman Institute of Microbiology, Rutgers University, New Jersey, USA St. Petersburg State Polytechnical University, St. Petersburg, Russia Institutes of Molecular Genetics and Gene Biology, Russian Academy of Sciences, Moscow, Russia Skolkovo Institute of Science and Technology, Skolkovo, Russia severik@waksman.rutgers.edu rob.lavigne@biw.kuleuven.be.
authors: Konstantin
authors: K
authors: Severinov
authors: Division of Gene Technology, KU Leuven, Heverlee, Belgium severik@waksman.rutgers.edu rob.lavigne@biw.kuleuven.be.
authors: Rob
authors: R
authors: Lavigne
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001435:Bacteriophages / Q000201:enzymology / Q000235:genetics / Q000254:growth & development* / Q000502:physiology; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism*; D015967:Gene Expression Regulation, Viral; D016679:Genome, Viral; D054884:Host-Pathogen Interactions; D017105:Pseudomonas Phages / Q000201:enzymology / Q000235:genetics / Q000254:growth & development* / Q000502:physiology; D011550:Pseudomonas aeruginosa / Q000201:enzymology* / Q000235:genetics / Q000821:virology; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism; D014779:Virus Replication
chemical_list: D001426:Bacterial Proteins; D014764:Viral Proteins; D012321:DNA-Directed RNA Polymerases