title: Molecular markers for discriminating Streptococcus pyogenes and S. dysgalactiae subspecies equisimilis.
abstract: Given the increasing aetiological importance of Streptococcus dysgalactiae subspecies equisimilis in diseases which are primarily attributed to S. pyogenes, molecular markers are essential to distinguish these species and delineate their epidemiology more precisely. Many clinical microbiology laboratories rely on agglutination reactivity and biochemical tests to distinguish them. These methods have limitations which are particularly exacerbated when isolates with mixed properties are encountered. In order to provide additional distinguishing parameters that could be used to unequivocally discriminate these two common pathogens, we assess here three molecular targets: the speB gene, intergenic region upstream of the scpG gene (IRSG) and virPCR. Of these, the former two respectively gave positive and negative results for S. pyogenes, and negative and positive results for S. dysgalactiae subsp. equisimilis. Thus, a concerted use of these nucleic acid-based methods is particularly helpful in epidemiological surveillance to accurately assess the relative contribution of these species to streptococcal infections and diseases.
authors.affiliation: Bacterial Pathogenesis Laboratory, The Queensland Institute of Medical Research, 300, Herston Road, Brisbane, QLD 4006, Australia.
authors.forename: D J
authors.initials: DJ
authors.lastname: McMillan
authors.forename: T
authors.initials: T
authors.lastname: Vu
authors.forename: P V
authors.initials: PV
authors.lastname: Bramhachari
authors.forename: S Y
authors.initials: SY
authors.lastname: Kaul
authors.forename: A
authors.initials: A
authors.lastname: Bouvet
authors.forename: M S
authors.initials: MS
authors.lastname: Shaila
authors.forename: M G
authors.initials: MG
authors.lastname: Karmarkar
authors.forename: K S
authors.initials: KS
authors.lastname: Sriprakash
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D003546:Cysteine Endopeptidases / Q000235:genetics; D003937:Diagnosis, Differential; D005819:Genetic Markers; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*; D013045:Species Specificity; D013290:Streptococcal Infections / Q000382:microbiology; D013291:Streptococcus / Q000145:classification* / Q000235:genetics; D013297:Streptococcus pyogenes / Q000145:classification / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D005819:Genetic Markers; D003546:Cysteine Endopeptidases; C042477:streptopain