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Updated: Jul 14, 2026
14:07
Genome-wide Gene Deletions in Streptococcus sanguinis by High Throughput PCR
Published on: November 23, 2012
Competence-induced fratricide in streptococci.
Jean-Pierre Claverys1, Bernard Martin, Leiv Sigve Håvarstein
1Laboratoire de Microbiologie et Génétique Moléculaires, UMR5100 CNRS-Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 09, France. claverys@ibcg.biotoul.fr
Molecular Microbiology
|June 9, 2007
Summary
Streptococcus pneumoniae uses a fratricide mechanism to acquire DNA from other pneumococci during natural genetic transformation. This process, controlled by competence-stimulating peptide (CSP), involves dispensable proteins and appears conserved across Streptococcus species.
Area of Science:
- Microbiology
- Genetics
- Molecular Biology
Background:
- Natural genetic transformation in Streptococcus pneumoniae is regulated by competence-stimulating peptide (CSP).
- CSP triggers the expression of competence (com) genes, some essential and others dispensable for DNA uptake.
- Dispensable com genes may have roles beyond direct transformation.
Purpose of the Study:
- To review evidence for the conservation of fratricide in Streptococcus species.
- To discuss the independent evolution of fratricide's genetic control and effectors.
- To explore the biological significance of fratricide in relation to natural transformation.
Main Methods:
- Literature review of studies on Streptococcus pneumoniae and other Streptococcus species.
- Analysis of genetic regulation and protein functions related to competence and fratricide.
- Comparative genomics and evolutionary analysis.
Main Results:
- Fratricide, a mechanism for competent cells to kill non-competent neighbors and acquire DNA, is linked to dispensable competence proteins in S. pneumoniae.
- Evidence suggests fratricide is conserved across several Streptococcus species.
- Genetic control and effector mechanisms of fratricide have evolved independently in different species.
Conclusions:
- Fratricide is a significant, albeit specialized, aspect of natural transformation in Streptococcus.
- Understanding fratricide provides insights into bacterial social behavior and DNA acquisition strategies.
- The conserved yet independently evolved nature of fratricide highlights its adaptive importance.
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