title: Detection of genes encoding internalization-associated proteins in Streptococcus pyogenes isolates from patients with invasive diseases and asymptomatic carriers.
abstract: A total of 161 Streptococcus pyogenes isolates from patients with invasive infections or from asymptomatic carriers were examined for genes (prtF1, prtF2, and fba) coding for fibronectin-binding proteins to evaluate their involvement in the pathogenesis of different streptococcal manifestations. We found no significant differences in the presence of these three genes between the two groups. Overall, the prtF2 gene was present in similar percentages among strains from both sources (61% versus 63%). Strains carrying the gene fba were slightly more common among those isolated from asymptomatic carriers (72.6% versus 65%). Also, the prtF1 gene was present in a higher, but not significant, percentage among strains from throat swabs than among isolates from invasive infections (75% versus 64.9%). However, this more detailed characterization of the genes encoding fibronectin-binding proteins allowed us to identify a strong association of genes of the erm class, coding for macrolide resistance, with prtF1 and prtF2 rather than with prtF1 alone. Since macrolide resistance was significantly associated with throat swab isolates, it may be hypothesized that proteins coded by prtF1 and prtF2 genes may be synergic in providing support for cell invasion and/or colonizing or persistence efficiency.
authors.affiliation: Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy. baldassa@iss.it
authors.forename: Lucilla
authors.initials: L
authors.lastname: Baldassarri
authors.forename: Roberta
authors.initials: R
authors.lastname: Creti
authors.forename: Monica
authors.initials: M
authors.lastname: Imperi
authors.forename: Simona
authors.initials: S
authors.lastname: Recchia
authors.forename: Marco
authors.initials: M
authors.lastname: Pataracchia
authors.forename: Graziella
authors.initials: G
authors.lastname: Orefici
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002353:Carrier State / Q000382:microbiology*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D005634:Fructose-Bisphosphate Aldolase; D005798:Genes, Bacterial; D006801:Humans; D018942:Macrolides / Q000494:pharmacology; D008780:Methyltransferases / Q000235:genetics; D013290:Streptococcal Infections / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity*; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D018829:Adhesins, Bacterial; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; C445329:Fba protein, Streptococcus pyogenes; D018942:Macrolides; D037521:Virulence Factors; C078635:fibronectin-binding proteins, bacterial; C111078:ErmTR protein, bacteria; D008780:Methyltransferases; D005634:Fructose-Bisphosphate Aldolase