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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

Molecular and biochemical analysis of the system regulating the lytic/lysogenic cycle in the pneumococcal temperate

Virginia Obregón1, Pedro García, Rubens López

  • 1Departamento de Microbiología Molecular, Centro de Investigaciones Biológicas, CSIC, Velázquez 144, 28006, Madrid, Spain.

FEMS Microbiology Letters
|May 29, 2003
PubMed

Insights

The temperate phage MM1 establishes stable lysogens in Streptococcus pneumoniae. Its 14-kDa cI protein (CI) maintains this lysogenic state by controlling divergent promoters P(R) and P(L).

Area of Science:

  • Microbiology
  • Bacteriology
  • Molecular Biology

Background:

  • Streptococcus pneumoniae is a significant human pathogen.
  • Temperate phages can integrate into bacterial genomes, forming lysogens.
  • Understanding phage-bacterial interactions is crucial for controlling infections.

Purpose of the Study:

  • To characterize the lysogenic control region of the temperate phage MM1 in Streptococcus pneumoniae.
  • To identify the key molecular components responsible for maintaining lysogeny.

Main Methods:

  • Genetic characterization of the MM1 phage genome.
  • Analysis of promoter activity (P(R) and P(L)).
  • Assessment of the function of the MM1 cI protein.

Main Results:

  • The lysogenic control region of MM1 contains two divergent promoters, P(R) and P(L).
  • MM1 encodes a 14-kDa cI protein (CI).
  • The cI protein prevents the elongation of transcripts from P(R) and P(L), indicating its role in lysogenic maintenance.

Conclusions:

  • The cI protein of phage MM1 is essential for maintaining the lysogenic state in Streptococcus pneumoniae.
  • This study provides the first characterization of the lysogenic control region in Pneumococcus.
  • The findings contribute to understanding phage-bacterial interactions and phage-mediated gene regulation.

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