Xinwu Wang 1, Hao Zhang 1, Lanting Bi 1, Hengyu Xi1, Zijing Wang 1, Yalu Ji 1, Xiao Liu 1, Rihong Zhao 1, Ming Liu1, Meimei Zhang1, Chunzheng Huang1, Hongda Ou1, Wenyu Han1,2, Jianbao Dong 3, Jingmin Gu1,4 and Wei Zhu 3*
1Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, P.R. China; 2Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou 225009, P.R. China; 3Department of Veterinary Medical Science, Shandong Vocational Animal Science and Veterinary College, Weifang 261061, P.R. China; 4Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, P.R. China
*Corresponding author: niccole522@hotmail.com
Phage therapy is a promising alternative therapy for treating E. coli infection. Although the total number of phages on the earth is as high as 1031, the reported phages and thoroughly studied are very limited. Therefore, the continuous discovery of new phages and in-depth research will provide materials for the wide application of phage therapy in the future. In this study, a novel E. coli phage vB_EcoM_011D4 was isolated from sewage samples, and the biological characteristics were studied. Electron microscopy and homology analysis results showed that vB_EcoM_011D4 belongs to the family Myoviridae. One-step growth curve showing the latent period of vB_EcoM_011D4 was 10min, with 115 PFU/cell burst size. Phage vB_EcoM_011D4 was highly stabled under different temperatures (range 4-70?) and pH conditions (range 6-10). At the same time, its genome was subjected to high-throughput sequencing and compared with the reported phages. The results of high-throughput sequencing assembly showed that vB_EcoM_011D4 is a linear, double-stranded DNA virus containing 163764 bp, with an average GC content of 40.50%, and a total of 273 open reading frames (ORFs). Genomic comparison analysis revealed that most ORFs were similar to Enterobacteria phage Phi1 and RB49. However, ORF147 and ORF148 putative DNA methylase family protein is less than 67% homology with already published phages. In addition, the phylogenetic analysis of terminates large subunit showed that it belongs to a new branch and shows less than 50 similarities to reported phages. No lysogenic, toxin, or antibiotic-resistant related gene was found in the genome of vB_EcoM_011D4. In summary, vB_EcoM_011D4 is a newly discovered phage that can be further studied to elucidate the phage diversity and its benefits for the wide application of phage therapy.