Complete genome analysis of , a species inhibiting O157:H7.

INTRODUCTION

Bacteriophages infecting human pathogens have been considered potential biocontrol agents, and studying their genetic content is essential to their safe use in the food industry. is a bacteriophage named UFV-AREG1, isolated from cowshed wastewater and previously tested for its ability to inhibit O157:H7.

METHODS

1 was previously isolated using E. O157:H7 (ATCC 43895) as a bacterial host. The same strain was used for bacteriophage propagation and the one-step growth curve. The genome of the T. ufvareg1 was sequenced using 305 Illumina HiSeq, and the genome comparison was calculated by VIRIDIC and VIPTree.

RESULTS

Here, we characterize its genome and compare it to other . virions have an icosahedral head (114 x 86 nm) and a contracted tail (117 x 23 nm), with a latent period of 25 min, and an average burst size was 18 phage particles per infected cell. The genome of the bacteriophage contains 268 coding DNA sequences (CDS) and ten tRNA genes distributed in both negative and positive strains. genome also contains 40 promoters on its regulatory regions and two rho-independent terminators. shares an average intergenomic similarity (VIRIDC) of 88.77% and an average genomic similarity score (VipTree) of 88.91% with eight four reference genomes for available in the NCBI RefSeq database. The pan-genomic analysis confirmed the high conservation of genomes. Among all CDS annotated in the genome, there are 123 core genes, 38 softcore genes, 94 shell genes, and 13 cloud genes. None of 268 CDS was classified as being exclusive of .

CONCLUSION

The results in this paper, combined with other previously published findings, indicate that bacteriophage is a potential candidate for food protection against O157:H7 in foods.