Reduced In VitroSusceptibility of Streptococcus pyogenesto ß-Lactam Antibiotics Associated with Mutations in the pbp2xGene Is Geographically Widespread

Recently, two related Streptococcus pyogenesstrains with reduced susceptibility to ampicillin, amoxicillin, and cefotaxime, antibiotics commonly used to treat S. pyogenesinfections, were reported. The two strains had the same nonsynonymous (amino acid-substituting) mutation in the pbp2xgene, encoding penicillin-binding protein 2X (PBP2X). This concerning report led us to investigate our library of 7,025 genome sequences of type emm1, emm28, and emm89S. pyogenesclinical strains recovered from intercontinental sources for mutations in pbp2x.