Dataset Information

Molecular subtyping of prevalent M serotypes of Streptococcus pyogenes causing invasive disease.

ABSTRACT: Reproducible methodologies and a scheme for high-resolution genotyping of Streptococcus pyogenes were defined with respect to a study of six predominant M serotypes causing invasive group A streptococcal disease in the United Kingdom. Serotype reference strains were compared with nine clinical isolates of each serotype from patients with diseases such as pneumonia, puerperal sepsis, toxic shock-like-syndrome, cellulitis, or necrotizing fasciitis. Four enzymes were evaluated for their discriminatory power in 16S rRNA gene-specific ribotyping. Discriminatory power was greatest with EcoRI, which generated serotype-specific ribotypes, and with SacI, which could subdivide strains of the same M serotype. Twenty-five combined ribotypes were found among the 60 strains, and the indices of discriminatory power (D values) of this method varied from 0.51 within serotype M1 to 0.98 within strains of serotype M5. Macrorestriction with the rarely cutting endonuclease SmaI and pulsed-field gel electrophoresis gave D values varying from 0.37 within serotype M1 to the maximal 1.0 within serotype M5. Comparison of macrorestriction profiles revealed various degrees of genetic heterogeneity within M serotypes. Strains of M1, M3, M6, and M11 exhibited clonally related macrorestriction profiles, while those of R28 and M5 strains were consistent with polyphyletic origin.

SUBMITTER: Stanley J

PROVIDER: S-EPMC228593 | biostudies-other | 1995 Nov

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Molecular subtyping of prevalent M serotypes of Streptococcus pyogenes causing invasive disease.

Stanley J J Linton D D Desai M M Efstratiou A A George R R

Journal of clinical microbiology 19951101 11

Reproducible methodologies and a scheme for high-resolution genotyping of Streptococcus pyogenes were defined with respect to a study of six predominant M serotypes causing invasive group A streptococcal disease in the United Kingdom. Serotype reference strains were compared with nine clinical isolates of each serotype from patients with diseases such as pneumonia, puerperal sepsis, toxic shock-like-syndrome, cellulitis, or necrotizing fasciitis. Four enzymes were evaluated for their discriminat ...[more]

PMID: 8576332

Similar Datasets

Project description:BackgroundStreptococcus pyogenes is a major cause of severe, invasive infections in humans. The bacterial pathogen harbors a wide array of virulence factors and exhibits high genomic diversity. Rapid changes of circulating strains in a community are common. Understanding the current prevalence and dynamics of S. pyogenes lineages could inform vaccine development and disease control strategies.MethodsWe used whole-genome sequencing (WGS) to characterize all invasive S. pyogenes isolates obtained through the United States Center for Disease Control and Prevention's Active Bacterial Core surveillance (ABCs) in 2016 and 2017. We determined the distribution of strain features, including emm type, antibiotic resistance determinants, and selected virulence factors. Changes in strain feature distribution between years 2016 and 2017 were evaluated. Phylogenetic analysis was used to identify expanding lineages within emm type.ResultsSeventy-one emm types were identified from 3873 isolates characterized. The emm types targeted by a 30-valent M protein-based vaccine accounted for 3230 (89%) isolates. The relative frequencies of emm types collected during the 2 years were similar. While all isolates were penicillin-susceptible, erythromycin-resistant isolates increased from 273 (16% of 2016 isolates) to 432 (23% of 2017 isolates), mainly driven by increase of the erm-positive emm types 92 and 83. The prevalence of 24 virulence factors, including 11 streptococcal pyrogenic toxins, ranged from 6 to 90%. In each of three emm types (emm 49, 82, and 92), a subgroup of isolates significantly expanded between 2016 and 2017 compared to isolates outside of the subgroup (P-values < 0.0001). Specific genomic sequence changes were associated with these expanded lineages.ConclusionsWhile the overall population structure of invasive S. pyogenes isolates in the United States remained stable, some lineages, including several that were antibiotic-resistant, increased between 2016 and 2017. Continued genomic surveillance can help monitor and characterize bacterial features associated with emerging strains from invasive infections.

Dataset Information

Molecular subtyping of prevalent M serotypes of Streptococcus pyogenes causing invasive disease.

Publications

Molecular subtyping of prevalent M serotypes of Streptococcus pyogenes causing invasive disease.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets