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Updated: May 13, 2026
08:51
Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR (RS-PCR)
Published on: November 4, 2016
Updated model of group A Streptococcus M proteins based on a comprehensive worldwide study
D J McMillan1, P-A Drèze, T Vu
1Bacterial Pathogenesis Laboratory, Queensland Institute of Medical Research, Brisbane, Qld, Australia.
Summary
Group A Streptococcus M protein diversity was analyzed globally. emm-type accurately predicts M protein structure, aiding vaccine development and understanding pathogenesis.
Area of Science:
- Microbiology
- Structural Biology
- Vaccinology
Background:
- Group A Streptococcus (GAS) M protein is a key virulence factor and vaccine target.
- Over 200 emm-types exist, but structural data is limited for most.
- Understanding M protein diversity is crucial for vaccine design and epidemiology.
Purpose of the Study:
- To evaluate sequence diversity of GAS M proteins globally.
- To analyze M protein structure, conservation, and classification.
- To inform vaccine development and pathogenesis studies.
Main Methods:
- Analysis of 1086 GAS isolates from 31 countries over two decades.
- emm-typing and complete emm gene sequencing.
- Bioinformatic analyses including amino acid sequence, secondary structure predictions, and epitope mapping.
Main Results:
- 175 emm-types were represented in the global isolate collection.
- emm-type was found to be predictive of M protein structure, irrespective of origin or clinical association.
- No emm-type was associated with multiple, highly divergent central regions.
Conclusions:
- M protein structure is conserved within an emm-type, supporting its use in classification.
- Global M protein data refines structural models (e.g., M6 updated to M5, M80, M77 models).
- Findings facilitate improved epidemiological analysis, vaccine development, and pathogenesis research.
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