Complete genome of a novel mycobacteriophage WXIN isolated in Wuhan, China

The rising of antibiotic resistance has sparked a renewed interest in mycobacteriophage as alternative therapeutic strategies against mycobacterial infections. So far, the vast majority of mycobacteriophages have been isolated using the model species Mycobacterium smegmatis, implying an overwhelming majority of mycobacteriophages in the environment remain uncultured, unclassified, and their specific hosts and infection strategies are still unknown. This study was undertaken to isolate and characterize novel mycobacteriophages targeting Mycobacterium septicum.

Here a novel mycobacteriophage WXIN against M. septicum was isolated from soil samples in Wuhan, China. Whole genome analysis indicates that the phage genome consists of 115,158 bp with a GC content of 61.9%. Of the 260 putative open reading frames, 46 may be associated with phage packaging, structure, lysis, lysogeny, genome modification/replication, and other functional roles. The limited genome-wide similarity, along with phylogenetic trees constructed based on viral proteome and orthologous genes show that phage WXIN represents a novel cluster distantly related to cluster J mycobacteriophages (genus Omegavirus). Overall, these results provide novel insights into the genomic properties of mycobacteriophages, highlighting the great genetic diversity of mycobacteriophages in relation to their hosts.