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Isolation and Genome Analysis of Single Virions using 'Single Virus Genomics'
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Isolation and Genome Analysis of Single Virions using 'Single Virus Genomics'

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Isolation, characterization and comparative genomics of bacteriophage SfIV: a novel serotype converting phage from

Richa Jakhetia1, Kaisar A Talukder, Naresh K Verma

  • 1Division of Biomedical Science and Biochemistry, Research School of Biology, The Australian National University, Bldg, 134 Linnaeus Way, Canberra ACT 0200, Australia. naresh.verma@anu.edu.au.

BMC Genomics
|October 5, 2013
PubMed
Abstract

Insights

A new bacteriophage, SfIV, was discovered that converts Shigella flexneri to serotype 4a. This phage possesses unique proteins potentially involved in host pathogenesis and survival, offering insights into phage evolution and therapeutic development.

Area of Science:

  • Microbiology
  • Virology
  • Genomics

Background:

  • Shigella flexneri causes shigellosis, with O-antigen modification crucial for its virulence.
  • Serotype conversion in S. flexneri is mediated by bacteriophages encoding modification genes.
  • Previous attempts to isolate phages for serotype 4a modification were unsuccessful.

Purpose of the Study:

  • To isolate and characterize a novel temperate bacteriophage capable of modifying S. flexneri serotype.
  • To determine the complete genome sequence of the isolated bacteriophage.
  • To compare the novel phage with existing S. flexneri phages and identify unique genetic elements.

Main Methods:

  • Isolation and characterization of a novel temperate bacteriophage (SfIV).
  • Lysogenization experiments to assess serotype conversion.
  • Electron microscopy for phage family identification.
  • Whole-genome sequencing and comparative genomic analysis.

Main Results:

  • Isolation of temperate bacteriophage SfIV, which converts serotype Y to 4a upon lysogenization.
  • SfIV belongs to the Myoviridae family and has a genome size of 39,758 bp with 54 open reading frames.
  • Comparative analysis revealed SfIV shares similarities with phages SfII and SfV but possesses five unique proteins, including a tail fiber assembly protein and hypothetical proteins.

Conclusions:

  • The study reports the isolation and complete genome analysis of bacteriophage SfIV.
  • SfIV exhibits a distinct host range and contains unique proteins potentially involved in S. flexneri pathogenesis.
  • Findings contribute to understanding phage evolution and developing phage-based therapeutics against S. flexneri infections.

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