Novel group of podovirus infecting the marine bacteriumAlteromonas macleodii.
Four novel, closely related podoviruses, which displayed lytic activity against the gamma-proteobacteriumAlteromonas macleodii,have been isolated and sequenced. Alterophages AltAD45-P1 to P4 were obtained from water recovered near a fish farm in the Mediterranean Sea. Their morphology indicates that they belong to thePodoviridae. Their linear and dsDNA genomes are 100-104 kb in size, remarkably larger than any other described podovirus. The four AltAD45-phages share 99% nucleotide sequence identity over 97% of their ORFs, although an insertion was found in AltAD45-P1 and P2 and some regions were slightly more divergent. Despite the high overall sequence similarity among these four phages, the group with the insertion and the group without it, have different host ranges against theA. macleodiistrains tested. The AltAD45-P1 to P4 phages have genes for DNA replication and transcription as well as structural genes, which are similar to the N4-likePodoviridaegenus that is widespread in proteobacteria. However, in terms of their genomic structure, AltAD45-P1 to P4 differ from that of the N4-like phages. Some distinguishing features include the lack of a large virion encapsidated RNA polymerase gene, very well conserved among all the previously described N4-like phages, a single-stranded DNA binding protein and different tail protein genes. We conclude that the AltAD45 phages characterized in this study constitute a new genus within thePodoviridae.
Evolutionary Genomics Group; División de Microbiología; Universidad Miguel Hernández; San Juan, Alicante Spain.
Inmaculada
I
Garcia-Heredia
Francisco
F
Rodriguez-Valera
Ana-Belen
AB
Martin-Cuadrado
Alteromonas macleodii; N4-like virus; Podoviridae; lytic phage; marine phages