Induction and Genome Analysis of HY01, a Newly Reported Prophage from an Emerging Shrimp Pathogen

is an emerging aquaculture pathogen that causes luminous vibriosis in farmed shrimp. Although prophages in various aquaculture pathogens have been widely reported, there is still limited knowledge regarding prophages in the genome of pathogenic . Here, we describe the full-genome sequence of a prophage named HY01, induced from the emerging shrimp pathogen HY01. The phage HY01 was induced by mitomycin C and was morphologically characterized as long tailed phage. phage HY01 is composed of 41,772 bp of dsDNA with a G+C content of 47.45%. A total of 60 open reading frames (ORFs) were identified, of which 31 could be predicted for their biological functions. Twenty seven out of 31 predicted protein coding regions were matched with several encoded proteins of various , , , and other phages of Gram-negative bacteria. Interestingly, the comparative genome analysis revealed that the phage HY01 was only distantly related to Vibrio phage Va_PF430-3_p42 of fish pathogen but differed in genomic size and gene organization. The phylogenetic tree placed the phage together with family. Additionally, a survey of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) spacers revealed two matching sequences between phage HY01 genome and viral spacer sequence of spp. The spacer results combined with the synteny results suggest that the evolution of phage HY01 is driven by the horizontal genetic exchange between bacterial families belonging to the class of Gammaproteobacteria.