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Updated: Aug 10, 2026
08:03
Heuristic Mining of Hierarchical Genotypes and Accessory Genome Loci in Bacterial Populations
Published on: December 7, 2021
Genomic diversity and evolution within the species Streptococcus agalactiae
Mathieu Brochet1, Elisabeth Couvé, Mohamed Zouine
1Unité de Génomique des Microorganismes Pathogènes-URA CNRS 2171, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France.
Microbes and Infection
|March 15, 2006
Summary
Streptococcus agalactiae exhibits significant genetic variation, impacting host interactions. The hypervirulent ST-17 lineage shows conserved surface proteins, explaining its neonatal infection capacity.
Area of Science:
- Microbiology
- Genomics
- Infectious Diseases
Background:
- Streptococcus agalactiae causes severe neonatal infections and bovine mastitis.
- It also asymptomatically colonizes human and animal genitourinary and gut tracts.
Purpose of the Study:
- To analyze genetic variations in Streptococcus agalactiae strains from human and animal origins.
- To investigate the genetic basis of the hypervirulence in the ST-17 lineage.
Main Methods:
- Serotyping
- Multilocus sequence typing
- Whole genome DNA-array hybridizations
- Sequence comparison of virulence-associated loci
Main Results:
- Significant genetic variations found in both genomic islands and the genome backbone.
- Recombination events drive evolution in surface and secreted protein genes, leading to diverse surface protein patterns.
- The hypervirulent ST-17 lineage is genetically homogeneous with a conserved set of surface proteins.
Conclusions:
- Genetic diversity in Streptococcus agalactiae influences host-pathogen interactions and immune evasion.
- Conserved surface proteins in the ST-17 lineage likely contribute to its high neonatal infection potential.
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