Isolation, characterization and genome sequencing of the novel phage SL25 from the Yellow Sea, China

Outnumbering all other biological entities on earth, bacteriophages play critical roles in structuring microbial communities. However, only a small number of phages have so far been reported. In this study, a novel Pseudoalteromonas phage, SL25, was isolated from the yellow sea, China. Transmission electron microscope observations showed that phage has an icosahedral head, 100 ± 1 nm in diameter, and a tail with a length of 150 ± 1 nm, and should be grouped into the Siphoviridae family. To better understand the genetic diversity of this phage, the complete genome was characterized. It consists 29,130-bp-length double-stranded DNA with a GC content of 41.04% and is predicted to have 61 open reading frames (ORFs) with an average length of 504 nucleotides. This study adds a new Siphoviridae phage to the marine bacteriophage dataset that could potentially infect Pseudoalteromonas. It also provides useful data for further molecular research on the interaction mechanism between bacteriophages and their hosts.