AUTHOR=Yang Chaojie , Wang Haiying  , Ma Hui , Bao Renlong , Liu Hongbo , Yang Lang , Liang Beibei , Jia Leili , Xie Jing , Xiang Ying , Dong Nian , Qiu Shaofu , Song Hongbin 

TITLE=Characterization and Genomic Analysis of SFPH2, a Novel T7virus Infecting Shigella

JOURNAL=Frontiers in Microbiology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2018.03027

DOI=10.3389/fmicb.2018.03027

ISSN=1664-302X

ABSTRACT=<p>Shigellosis, caused by <italic>Shigella</italic>, is a major global health concern, with nearly 164.7 million cases and over a million deaths occurring annually worldwide. <italic>Shigella flexneri</italic> is one of the most common subgroups of <italic>Shigella</italic> with a high incidence of multidrug-resistance. The phage therapy approach is an effective method for controlling multidrug-resistant bacteria. However, only a few <italic>Shigella</italic> phages have been described to date. In this study, a novel lytic bacteriophage SFPH2 was isolated from a sewage sample obtained from a hospital in Beijing, China, using a multidrug-resistant <italic>S. flexneri</italic> 2a strain (SF2) isolated from the fecal sample of a dysentery patient. SFPH2 is a member of the <italic>Podoviridae</italic> virus family with an icosahedral capsid and a short, non-contractile tail. It was found to be stable over a wide range of temperatures (4–50°C) and pH values (pH 3–11). Moreover, SFPH2 could infect two other <italic>S. flexneri</italic> serotypes (serotypes 2 variant and Y). High-throughput sequencing revealed that SFPH2 has a linear double-stranded DNA genome of 40,387 bp with 50 open reading frames. No tRNA genes were identified in the genome. Comparative analysis of the genome revealed that the SFPH2 belongs to the subfamily <italic>Autographivirinae</italic> and genus <italic>T7virus</italic>. The genome shows high similarity with other enterobacterial <italic>T7virus</italic> bacteriophages such as <italic>Citrobacter</italic> phage SH4 (95% identity and 89% coverage) and <italic>Cronobacter</italic> phage Dev2 (94% identity and 92% coverage). A comparison of the fiber proteins showed that minor differences in the amino acid residues might specify different protein binding regions and determine host species. In conclusion, this is the first report of a <italic>T7virus</italic> that can infect <italic>Shigella</italic>; SFPH2 has a functional stability under a wide range of temperatures and pH values, showing the potential to be widely applied to control <italic>Shigella</italic>–associated clinical infections and reduce the transmission rates of <italic>S. flexneri</italic> serotype 2a and its variants in the environment.</p>