title: Characterization of the genome of the dairy Lactobacillus helveticus bacteriophage {Phi}AQ113.
abstract: The complete genomic sequence of the dairy Lactobacillus helveticus bacteriophage ΦAQ113 was determined. Phage ΦAQ113 is a Myoviridae bacteriophage with an isometric capsid and a contractile tail. The final assembled consensus sequence revealed a linear, circularly permuted, double-stranded DNA genome with a size of 36,566 bp and a G+C content of 37%. Fifty-six open reading frames (ORFs) were predicted, and a putative function was assigned to approximately 90% of them. The ΦAQ113 genome shows functionally related genes clustered together in a genome structure composed of modules for DNA replication/regulation, DNA packaging, head and tail morphogenesis, cell lysis, and lysogeny. The identification of genes involved in the establishment of lysogeny indicates that it may have originated as a temperate phage, even if it was isolated from natural cheese whey starters as a virulent phage, because it is able to propagate in a sensitive host strain. Additionally, we discovered that the ΦAQ113 phage genome is closely related to Lactobacillus gasseri phage KC5a and Lactobacillus johnsonii phage Lj771 genomes. The phylogenetic similarities between L. helveticus phage ΦAQ113 and two phages that belong to gut species confirm a possible common ancestral origin and support the increasing consideration of L. helveticus as a health-promoting organism.
authors.affiliation: Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Centro di Ricerca per le Produzioni Foraggere e Lattiero-Casearie, Lodi, Italy. miriam.zago@entecra.it
authors.forename: Miriam
authors.initials: M
authors.lastname: Zago
authors.forename: Erika
authors.initials: E
authors.lastname: Scaltriti
authors.forename: Lia
authors.initials: L
authors.lastname: Rossetti
authors.forename: Alessandro
authors.initials: A
authors.lastname: Guffanti
authors.forename: Angelarita
authors.initials: A
authors.lastname: Armiento
authors.forename: Maria Emanuela
authors.initials: ME
authors.lastname: Fornasari
authors.forename: Stefano
authors.initials: S
authors.lastname: Grolli
authors.forename: Domenico
authors.initials: D
authors.lastname: Carminati
authors.forename: Elena
authors.initials: E
authors.lastname: Brini
authors.forename: Paolo
authors.initials: P
authors.lastname: Pavan
authors.forename: Armando
authors.initials: A
authors.lastname: Felsani
authors.forename: Annalisa
authors.initials: A
authors.lastname: D'Urzo
authors.forename: Anna
authors.initials: A
authors.lastname: Moles
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Claude
authors.forename: Rita
authors.initials: R
authors.lastname: Grandori
authors.forename: Roberto
authors.initials: R
authors.lastname: Ramoni
authors.forename: Giorgio
authors.initials: G
authors.lastname: Giraffa
mesh_terms: D001482:Base Composition; D004279:DNA, Viral / Q000235:genetics* / Q000378:metabolism; D016679:Genome, Viral; D052198:Lactobacillus helveticus / Q000821:virology*; D008969:Molecular Sequence Data; D017900:Myoviridae / Q000145:classification / Q000235:genetics* / Q000648:ultrastructure; D016366:Open Reading Frames; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D004279:DNA, Viral