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Updated: Feb 10, 2026

Methodology for the Study of Horizontal Gene Transfer in Staphylococcus aureus
Published on: March 10, 2017
The effect of vaginal microbial communities on colonization by Staphylococcus aureus with the gene for toxic shock
Jacob D Pierson1, Melanie A Hansmann2, Catherine C Davis2
1Institute for Bioinformatics and Evolutionary Studies and Department of Biological Sciences University of Idaho, Moscow, ID 83844-3051, USA.
Abstract:
Menstrual toxic shock syndrome is associated with vaginal colonization by Staphylococcus aureus strains that encode toxic shock syndrome toxin 1 (tst+). Interestingly, a small proportion of women are colonized by S. aureus tst+ but do not have symptoms of toxic shock syndrome. Here we sought to determine if differences in the species composition of vaginal bacterial communities reflect a differential risk of colonization by S. aureus capable of producing toxic shock syndrome toxin 1 (TSST-1). The composition of vaginal communities of women that were or were not colonized with S. aureus tst+ were compared based on terminal restriction fragment length polymorphism (T-RFLP) profiles and sequences of cloned 16S rRNA genes. There were no detectable differences in community composition or species rank abundance between communities of women vaginally colonized with S. aureus tst+ as compared to those that were not. Phylogenetic analysis of cloned 16S rRNA gene sequences showed that the predominant members of communities of women colonized with S. aureus tst+ were indistinguishable from those of other healthy women. The data suggest that the numerically dominant members of vaginal communities do not preclude colonization and proliferation of S. aureus tst+ within indigenous microbial communities of the vagina.
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