title: Complete genome of the broad-host-range Erwinia amylovora phage phiEa21-4 and its relationship to Salmonella phage felix O1.
abstract: The first complete genome sequence for a myoviridal bacteriophage, PhiEa21-4, infecting Erwinia amylovora, Erwinia pyrifoliae, and Pantoea agglomerans strains has been determined. The unique sequence of this terminally redundant, circularly permuted genome is 84,576 bp. The PhiEa21-4 genome has a GC content of 43.8% and contains 117 putative protein-coding genes and 26 tRNA genes. PhiEa21-4 is the first phage in which a precisely conserved rho-independent terminator has been found dispersed throughout the genome, with 24 copies in all. Also notable in the PhiEa21-4 genome are the presence of tRNAs with six- and nine-base anticodon loops, the absence of a small packaging terminase subunit, and the presence of nadV, a principle component of the NAD(+) salvage pathway, which has been found in only a few phage genomes to date. PhiEa21-4 is the first reported Felix O1-like phage genome; 56% of the predicted PhiEa21-4 proteins share homology with those of the Salmonella phage. Apart from this similarity to Felix O1, the PhiEa21-4 genome appears to be substantially different, both globally and locally, from previously reported sequences. A total of 43 of the 117 genes are unique to PhiEa21-4, and 32 of the Felix O1-like genes do not appear in any phage genome sequences other than PhiEa21-4 and Felix O1. N-terminal sequencing and matrix-assisted laser desorption ionization-time of flight analysis resulted in the identification of five PhiEa21-4 genes coding for virion structural proteins, including the major capsid protein.
authors.affiliation: Department of Biological Science, Brock University, 500 Glenridge Avenue, St. Catharines, Ontario L2S 3A1, Canada.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Lehman
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Kropinski
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Castle
authors.forename: Antonet M
authors.initials: AM
authors.lastname: Svircev
mesh_terms: D001435:Bacteriophages / Q000235:genetics* / Q000302:isolation & purification / Q000648:ultrastructure; D001482:Base Composition; D004270:DNA, Circular / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics*; D044084:Erwinia amylovora / Q000821:virology*; D016679:Genome, Viral; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D012343:RNA, Transfer / Q000235:genetics; D012483:Salmonella Phages / Q000235:genetics; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D026801:Synteny; D014764:Viral Proteins / Q000235:genetics; D014771:Virion / Q000648:ultrastructure
chemical_list: D004270:DNA, Circular; D004279:DNA, Viral; D014764:Viral Proteins; D012343:RNA, Transfer