Streptococcus pyogenes causing toxic-shock-like syndrome and other invasive diseases: clonal diversity and pyrogenic exotoxin expression.
Genetic diversity and relationships among 108 isolates of the bacterium Streptococcus pyogenes recently recovered from patients in the United States with toxic-shock-like syndrome or other invasive diseases were estimated by multilocus enzyme electrophoresis. Thirty-three electrophoretic types (ETs), representing distinctive multilocus clonal genotypes, were identified, but nearly half the disease episodes, including more than two-thirds of the cases of toxic-shock-like syndrome, were caused by strains of two related clones (ET 1 and ET 2). These two clones were also represented by recent pathogenic European isolates. A previous report of a relatively high frequency of expression of exotoxin A among isolates recovered from toxic-shock-like syndrome patients in the United States was confirmed; and the demonstration of this association both within clones and among distantly related clones supports the hypothesis that exotoxin A is a causal factor in pathogenesis of this disease. Near identity of the nucleotide sequences of the exotoxin A structural gene of six isolates of five ETs in diverse phylogenetic lineages was interpreted as evidence that the gene has been horizontally distributed among clones, presumably by bacteriophage-mediated transfer.
Musser
J M
JM
Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, Philadelphia 19104.
Hauser
A R
AR
Kim
M H
MH
Schlievert
P M
PM
Nelson
K
K
Selander
R K
RK
D001426:Bacterial Proteins; D001483:Base Sequence; D004798:Enzymes / Q000235:genetics / Q000302:isolation & purification; D005060:Europe; D005098:Exotoxins / Q000235:genetics*; D005798:Genes, Bacterial; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D012772:Shock, Septic / Q000382:microbiology*; D013290:Streptococcal Infections / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D014481:United States
D001426:Bacterial Proteins; D004798:Enzymes; D005098:Exotoxins; D008565:Membrane Proteins; D015345:Oligonucleotide Probes; C117980:SpeA protein, Streptococcus pyogenes; C027951:erythrogenic toxin