title: The role of prophage-like elements in the diversity of Salmonella enterica serovars.
abstract: The Salmonella enterica serovar Typhi CT18 (S.Typhi) chromosome harbours seven distinct prophage-like elements, some of which may encode functional bacteriophages. In silico analyses were used to investigate these regions in S.Typhi CT18, and ultimately compare these integrated bacteriophages against 40 other Salmonella isolates using DNA microarray technology. S.Typhi CT18 contains prophages that show similarity to the lambda, Mu, P2 and P4 bacteriophage families. When compared to other S.Typhi isolates, these elements were generally conserved, supporting a clonal origin of this serovar. However, distinct variation was detected within a broad range of Salmonella serovars; many of the prophage regions are predicted to be specific to S.Typhi. Some of the P2 family prophage analysed have the potential to carry non-essential "cargo" genes within the hyper-variable tail region, an observation that suggests that these bacteriophage may confer a level of specialisation on their host. Lysogenic bacteriophages therefore play a crucial role in the generation of genetic diversity within S.enterica.
authors.affiliation: The Pathogen Sequencing Unit, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, United Kingdom. nrt@sanger.ac.uk
authors.forename: Nicholas
authors.initials: N
authors.lastname: Thomson
authors.forename: Stephen
authors.initials: S
authors.lastname: Baker
authors.forename: Derek
authors.initials: D
authors.lastname: Pickard
authors.forename: Maria
authors.initials: M
authors.lastname: Fookes
authors.forename: Muna
authors.initials: M
authors.lastname: Anjum
authors.forename: Nancy
authors.initials: N
authors.lastname: Hamlin
authors.forename: John
authors.initials: J
authors.lastname: Wain
authors.forename: Deborah
authors.initials: D
authors.lastname: House
authors.forename: Zulfiqar
authors.initials: Z
authors.lastname: Bhutta
authors.forename: Kaman
authors.initials: K
authors.lastname: Chan
authors.forename: Stanley
authors.initials: S
authors.lastname: Falkow
authors.forename: Julian
authors.initials: J
authors.lastname: Parkhill
authors.forename: Martin
authors.initials: M
authors.lastname: Woodward
authors.forename: Al
authors.initials: A
authors.lastname: Ivens
authors.forename: Gordon
authors.initials: G
authors.lastname: Dougan
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D017931:DNA Primers; D016680:Genome, Bacterial; D008969:Molecular Sequence Data; D039002:Prophages / Q000737:chemistry*; D012483:Salmonella Phages / Q000737:chemistry*; D019779:Salmonella enterica / Q000235:genetics / Q000821:virology*; D017386:Sequence Homology, Amino Acid
chemical_list: D017931:DNA Primers