Evolutionary origin and emergence of a highly successful clone of serotype M1 group a Streptococcus involved multiple horizontal gene transfer events

J Infect Dis. 2005 Sep 1;192(5):771-82. doi: 10.1086/432514. Epub 2005 Jul 29.


To better understand the molecular events involved in the origin of new pathogenic bacteria, we studied the evolution of a highly virulent clone of serotype M1 group A Streptococcus (GAS). Genomic, DNA-DNA microarray, and single-nucleotide polymorphism analyses indicated that this clone evolved through a series of horizontal gene transfer events that involved (1) the acquisition of prophages encoding streptococcal pyrogenic exotoxin A and extracellular DNases and (2) the reciprocal recombination of a 36-kb chromosomal region encoding the extracellular toxins NAD+-glycohydrolase (NADase) and streptolysin O (SLO). These gene transfer events were associated with significantly increased production of SLO and NADase. Virtual identity in the 36-kb region present in contemporary serotype M1 and M12 isolates suggests that a serotype M12 strain served as the donor of this region. Multiple horizontal gene transfer events were a crucial factor in the evolutionary origin and emergence of a very abundant contemporary clone of serotype M1 GAS.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Antigens, Bacterial / genetics
  • Bacterial Outer Membrane Proteins / genetics
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Base Sequence
  • Carrier Proteins / genetics
  • Clone Cells
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • Gene Transfer, Horizontal / genetics*
  • Genome, Bacterial*
  • Humans
  • Molecular Sequence Data
  • NAD+ Nucleosidase / genetics
  • NAD+ Nucleosidase / metabolism
  • Nucleic Acid Hybridization
  • Oligonucleotide Array Sequence Analysis
  • Phylogeny
  • Polymorphism, Single Nucleotide / genetics
  • Sequence Analysis, DNA
  • Streptococcal Infections / genetics
  • Streptococcal Infections / microbiology*
  • Streptococcus pyogenes / enzymology
  • Streptococcus pyogenes / genetics*
  • Streptolysins / genetics
  • Streptolysins / metabolism


  • Antigens, Bacterial
  • Bacterial Outer Membrane Proteins
  • Bacterial Proteins
  • Carrier Proteins
  • DNA, Bacterial
  • Streptolysins
  • streptococcal M protein
  • streptolysin O
  • NAD+ Nucleosidase