Partial biological characteristics and genomic analysis of Vibrio cholerae typing phage VP2

  Objective   To further understand the biological characteristics of Vibrio cholerae typing phage VP2 by analyzing its whole genome proteome and proliferation.

  Methods   The morphology of phage VP2 was observed under electron microscope, and the optimal multiplicity of infection (MOI) and one step growth curve were determined. Online RAST (https://rast.nmpdr.org/) was used to predict and annotate the encoding genes of the phage VP2 genome, and the proteins in the mature VP2 particles were analyzed by mass spectrometry. Phage genome average nucleotide consistency was analysis by using pyani.

  Results   Phage VP2 was a typical 20-hedron short-tailed phage, the optimal MOI was 0.01. One step growth curve showed that incubation period of about 60 minutes, outbreak period of 60–120 minutes was, and the stable period was after 120 minutes. Forty-nine open reading frames (ORFs) were predicted. Protein spectrum analysis of mature VP2 particles showed that 34 proteins corresponded to the predicted genes. Ani cluster analysis showed that Ani was the highest in VP2 and Vibro phage CJY.

  Conclusion   The biological and genomic characteristics of typing phage VP2 were identified and the protein of mature particles was obtained in this study, providing basic data for the further study of homologous phages and its interaction with V. cholerae.