Complete genomic sequence of bacteriophage felix o1

Abstract

Bacteriophage O1 is a Myoviridae A1 group member used historically for identifying Salmonella. Sequencing revealed a single, linear, 86,155-base-pair genome with 39% average G+C content, 131 open reading frames, and 22 tRNAs. Closest protein homologs occur in Erwinia amylovora phage φEa21-4 and Escherichia coli phage wV8. Proteomic analysis indentified structural proteins: Gp23, Gp36 (major tail protein), Gp49, Gp53, Gp54, Gp55, Gp57, Gp58 (major capsid protein), Gp59, Gp63, Gp64, Gp67, Gp68, Gp69, Gp73, Gp74 and Gp77 (tail fiber). Based on phage-host codon differences, 7 tRNAs could affect translation rate during infection. Introns, holin-lysin cassettes, bacterial toxin homologs and host RNA polymerase-modifying genes were absent.

Keywords: DNA sequence; Felix O1; Myoviridae; Salmonella; bacteriophage; bioinformatics.

Figure 1

Genetic and physical map of phage Felix O1 prepared using DNAPlotter [20] with, from outer to inner rings, the size in kb; genes on the forward and reverse strands with some of the genes listed in italics (N.B. gene 1 = rIIA), and tRNA-encoding genes (black). The inner circles correspond to a GC plot (purple, below average GC-content; greenish-brown) and a GC skew analysis. Genes involved in nucleotide metabolism or DNA replication are indicated in dark blue, those involved in DNA packaging and morphogenesis in red; and, the lysis gene in dark green.

Figure 2

Mauve alignment of the genomes of phages Felix O1 (top), wV8 (middle) and φEa21-4 (bottom). The degree of DNA sequence similarity is indicated by the height of the red-coloured regions. Just above the phage names are box-like diagrams indicating the position of the genes.

Figure 3

SDS-PAGE (10%) analysis of the structural proteins of Felix O1 with the masses of the Fermentas PageRuler markers (left) and the most abundant proteins (right).