Journal article

Updated emm -typing protocol for Streptococcus pyogenes

HR Frost, MR Davies, S Velusamy, V Delforge, A Erhart, S Darboe, A Steer, MJ Walker, B Beall, A Botteaux, PR Smeesters

Clinical Microbiology and Infection | ELSEVIER SCI LTD | Published : 2020


OBJECTIVES: PCR-based typing of the emm gene Streptococcus pyogenes often results in the amplification of multiple bands. This has resulted in the misclassification of strains into types based on non-emm gene sequences. We aimed to improve the specificity of the emm typing PCR reaction using a primer called CDC3, the sequence for which has been previously used to identify emm genes in silico. METHODS: The proposed primer CDC3 was validated in silico from a global database of 1688 GAS genomes and in vitro with 32 isolates. PCR reactions were performed on genomic DNA from each isolate, using the published CDC1 forward primer with the CDC2 reverse primer or the new CDC3 reverse primer. The prod..

View full abstract


Awarded by Belgian Fonds National de la Recherche Scientifique

Funding Acknowledgements

The authors do not declare any conflicts of interest. This work was supported by the Belgian Fonds National de la Recherche Scientifique research grants (PDR T.0255.16 and CDR J.0019.17). H.R.F. is supported by a Ph.D. fellowship granted by the Royal Academy of Medicine from Belgium and sponsored by GSK Vaccines. The funders had no role in study design and analysis.