Article

emm Gene distribution among erythromycin-resistant and -susceptible Italian isolates of Streptococcus pyogenes.

Department of Molecular Cellular Animal Biology, University of Camerino, 62032 Camerino, Italy.
Journal of Clinical Microbiology (impact factor: 4.15). 04/2003; 41(3):1307-10. pp.1307-10
Source: PubMed

ABSTRACT The phenotypes and genetic determinants for macrolide resistance were determined for 167 erythromycin-resistant Streptococcus pyogenes strains. A cMLS phenotype was shown in 18% of the erythromycin-resistant strains, while inducible resistance was apparent in 31% and the M phenotype was apparent in 50%. The emm gene type of this set of resistant isolates and that of 48 erythromycin-sensitive isolates were determined. emm2 and emm48 were recorded only in the resistant strains of the M phenotype, while approximately all of the strains harboring the emm22 gene had the cMLS phenotype. More than 80% of the emm89-positive strains had the iMLS phenotype, and the same portion of emm4 strains presented the M phenotype. emm3 is recorded only among sensitive strains. The distribution of frequencies of the genetic determinant for the virulence factor M protein was significantly different both among organisms of different types of resistance and between resistant and sensitive populations of S. pyogenes under study.

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

167 erythromycin-resistant Streptococcus pyogenes strains
 
48 erythromycin-sensitive
 
different types
 
emm gene type
 
emm2
 
emm22 gene
 
emm3
 
emm4 strains
 
emm89-positive strains
 
erythromycin-resistant strains
 
genetic determinant
 
genetic determinants
 
iMLS phenotype
 
inducible resistance
 
M phenotype
 
resistant strains
 
S. pyogenes
 
sensitive populations
 
sensitive strains
 
virulence factor M protein