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Updated: Oct 10, 2026

Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
08:58

Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes

Published on: March 3, 2023

Erythromycin resistance genes in group A streptococci of different geographical origins. The Macrolide Resistance

J Kataja1, P Huovinen, H Seppälä

  • 1Antimicrobial Research Laboratory, National Public Health Institute, PO Box 57, 20521 Turku, Finland. janne.kataja@utu.fi

The Journal of Antimicrobial Chemotherapy
|November 4, 2000
PubMed

Insights

Erythromycin-resistant Streptococcus pyogenes strains carrying the mefA gene were found globally. The ermTR gene was also widely distributed, indicating significant macrolide resistance mechanisms in this bacterium.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Epidemiology

Background:

  • Streptococcus pyogenes is a significant human pathogen.
  • Erythromycin resistance in S. pyogenes is a growing public health concern.
  • Understanding resistance mechanisms is crucial for effective treatment.

Purpose of the Study:

  • To investigate the prevalence and genetic basis of erythromycin resistance in Streptococcus pyogenes isolates.
  • To determine the geographic distribution of specific resistance genes.
  • To analyze the relationship between resistance genes and resistance phenotypes.

Main Methods:

  • Antibiotic susceptibility testing was performed on 238 S. pyogenes isolates from eight countries.
  • Molecular methods (gene detection) were used to identify resistance genes in 92 isolates.
  • Isolates were characterized based on clonal origin and resistance phenotypes.

Main Results:

  • The mefA gene was detected in all 54 isolates exhibiting the M-phenotype across all studied countries.
  • The ermTR and ermB genes were found in 27 and 11 isolates, respectively, with macrolide-lincosamide-streptogramin B resistance.
  • The mefA and ermTR genes were widely distributed among isolates of diverse clonal origins.

Conclusions:

  • The mefA gene is a primary determinant of the M-phenotype erythromycin resistance in S. pyogenes globally.
  • The ermTR gene is also a significant and widely distributed resistance gene in this pathogen.
  • These findings highlight the extensive dissemination of macrolide resistance mechanisms in Streptococcus pyogenes.

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