title: Group A streptococci from a remote community have novel multilocus genotypes but share emm types and housekeeping alleles with isolates from worldwide sources.
abstract: Group A streptococci (GAS) cause several human diseases that differentially affect distinct host populations. Genotypes were defined by multilocus sequence typing and emm typing for 137 organisms collected from individuals in a remote aboriginal island community in tropical Australia and compared with >200 isolates obtained from sources elsewhere in the world. The majority of aboriginal-derived isolates shared emm types and housekeeping alleles with GAS isolates recovered from outside Australia, but these emm types and alleles were in novel combinations. There were many examples in which isolates from aboriginal and non-Australian subjects shared the same emm type, but for approximately 50% of emm types, the multilocus genotypes of isolates of the same emm type but from different regions were very different. A single emm type may typically define a single clone within the United States and on the remote island that is the focus of this study, but in many cases, these clones will be different, and this finding has implications for attempts to make global associations between emm types and certain disease manifestations.
authors.affiliation: Department of Infectious Disease Epidemiology, Imperial College, London, United Kingdom.
authors.forename: Karen F
authors.initials: KF
authors.lastname: McGregor
authors.forename: Nicole
authors.initials: N
authors.lastname: Bilek
authors.forename: Alicia
authors.initials: A
authors.lastname: Bennett
authors.forename: Awdhesh
authors.initials: A
authors.lastname: Kalia
authors.forename: Bernard
authors.initials: B
authors.lastname: Beall
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Carapetis
authors.forename: Bart J
authors.initials: BJ
authors.lastname: Currie
authors.forename: Kadaba S
authors.initials: KS
authors.lastname: Sriprakash
authors.forename: Brian G
authors.initials: BG
authors.lastname: Spratt
authors.forename: Debra E
authors.initials: DE
authors.lastname: Bessen
mesh_terms: D001315:Australia; D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques; D002352:Carrier Proteins / Q000235:genetics; D005838:Genotype; D006801:Humans; D010139:Pacific Islands; D013290:Streptococcal Infections / Q000382:microbiology; D013297:Streptococcus pyogenes / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; C088687:EMM 9 protein, Streptococcus pyogenes