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Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
09:40

Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins

Published on: June 11, 2015

Genomic organization and molecular analysis of the inducible prophage EJ-1, a mosaic myovirus from an atypical

Patricia Romero1, Rubens López, Ernesto García

  • 1Departamento de Microbiología Molecular, Centro de Investigaciones Biológicas, CSIC, 28040 Madrid, Spain.

Virology
|April 28, 2004
PubMed

Insights

We sequenced the EJ-1 prophage from Streptococcus pneumoniae, revealing its genome structure and protein functions. This study expands knowledge of myoviruses infecting Gram-positive bacteria, including human pathogens.

Area of Science:

  • Microbiology
  • Virology
  • Genomics

Background:

  • Streptococcus pneumoniae is a significant human pathogen.
  • Bacteriophages (phages) are viruses that infect bacteria and play roles in bacterial evolution and ecology.
  • Myoviridae is a family of bacteriophages characterized by contractile tails.

Purpose of the Study:

  • To determine the complete genomic sequence of the EJ-1 prophage.
  • To identify and characterize the genes and encoded proteins of the EJ-1 prophage.
  • To understand the evolutionary relationships of EJ-1 with other phages.

Main Methods:

  • Whole-genome sequencing of the EJ-1 prophage.
  • Bioinformatic analysis of the genome, including Open Reading Frame (ORF) identification.
  • N-terminal amino acid sequence analysis for protein function prediction.
  • Comparative genomics to analyze similarities with other known phages.

Main Results:

  • The complete genome sequence of the EJ-1 prophage was determined (42935 bp), containing 73 ORFs organized into at least five clusters.
  • Functional assignments were made for 52 ORFs, revealing similarities to siphoviruses in lysogeny, DNA replication, and morphogenesis.
  • Unusual similarities were found in tail protein genes (orf53-orf64) to Bacillus subtilis myovirus PBSX, with a unique tape measure protein gene (orf56) similar to phages of Gram-negative bacteria.

Conclusions:

  • This is the first report of a myovirus genome infecting a low G+C Gram-positive bacterium.
  • The findings provide insights into phage biology and evolution, particularly concerning phages of important human pathogens.
  • The unique genetic makeup of EJ-1 highlights phage diversity and adaptation strategies.

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