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Genomic analysis of a Streptococcus pyogenes strain causing endocarditis in a child
M Beye1, K El Karkouri1, N Labas1
1URMITE, UM63, CNRS7278, IRD198, Inserm1095, Institut Hospitalo-Universitaire Méditerranée-infection, Aix-Marseille Université, Faculté de Médecine, Marseille, France.
New Microbes and New Infections
|February 28, 2017
Summary
Genome sequencing of Streptococcus pyogenes strain G773 revealed key virulence factors, including a complete integrative and conjugative element and bacteriocin genes. This strain, causing infective endocarditis, notably lacked a CRISPR-Cas system.
Area of Science:
- Microbiology
- Genomics
- Infectious Diseases
Background:
- Streptococcus pyogenes is a significant human pathogen.
- Infective endocarditis is a serious infection of the heart lining.
- Understanding pathogen genomes is crucial for developing effective treatments.
Purpose of the Study:
- To sequence and analyze the genome of Streptococcus pyogenes strain G773.
- To identify virulence factors contributing to infective endocarditis.
- To investigate the presence or absence of specific genetic elements like CRISPR-Cas systems.
Main Methods:
- Whole-genome sequencing of Streptococcus pyogenes strain G773.
- Bioinformatic analysis to identify genes and genetic elements.
- Comparative genomics to assess the completeness of known elements.
Main Results:
- The 1.9-Mb genome of strain G773 was fully sequenced.
- A complete integrative and conjugative element (sp2905) and five bacteriocin genes were identified.
- The absence of a CRISPR-Cas system in strain G773 was confirmed.
Conclusions:
- The genome of Streptococcus pyogenes strain G773 possesses a unique combination of virulence factors.
- The complete sp2905 element may play a role in the pathogenicity of this strain.
- The lack of a CRISPR-Cas system in this endocarditis-causing strain warrants further investigation.
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