• myGriffith
    • Staff portal
    • Contact Us⌄
      • Future student enquiries 1800 677 728
      • Current student enquiries 1800 154 055
      • International enquiries +61 7 3735 6425
      • General enquiries 07 3735 7111
      • Online enquiries
      • Staff phonebook
    View Item 
    •   Home
    • Griffith Research Online
    • Journal articles
    • View Item
    • Home
    • Griffith Research Online
    • Journal articles
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

  • All of Griffith Research Online
    • Communities & Collections
    • Authors
    • By Issue Date
    • Titles
  • This Collection
    • Authors
    • By Issue Date
    • Titles
  • Statistics

  • Most Popular Items
  • Statistics by Country
  • Most Popular Authors
  • Support

  • Contact us
  • FAQs
  • Admin login

  • Login
  • Ureaplasma parvum Undergoes Selection In Utero Resulting in Genetically Diverse Isolates Colonizing the Chorioamnion of Fetal Sheep

    Author
    Dando, Samantha
    Nitsos, Ilias
    R. Polglase, Graeme
    P. Newnham, John
    H. Jobe, Alan
    L. Knox, Christine
    Year published
    2014
    Metadata
    Show full item record
    Abstract
    Ureaplasmas are the microorganisms most frequently isolated from the amniotic fluid of pregnant women and can cause chronic intrauterine infections. These tiny bacteria are thought to undergo rapid evolution and exhibit a hypermutatable phenotype; however, little is known about how ureaplasmas respond to selective pressures in utero. Using an ovine model of chronic intraamniotic infection, we investigated if exposure of ureaplasmas to subinhibitory concentrations of erythromycin could induce phenotypic or genetic indicators of macrolide resistance. At 55 days gestation, 12 pregnant ewes received an intraamniotic injection ...
    View more >
    Ureaplasmas are the microorganisms most frequently isolated from the amniotic fluid of pregnant women and can cause chronic intrauterine infections. These tiny bacteria are thought to undergo rapid evolution and exhibit a hypermutatable phenotype; however, little is known about how ureaplasmas respond to selective pressures in utero. Using an ovine model of chronic intraamniotic infection, we investigated if exposure of ureaplasmas to subinhibitory concentrations of erythromycin could induce phenotypic or genetic indicators of macrolide resistance. At 55 days gestation, 12 pregnant ewes received an intraamniotic injection of a nonclonal, clinical Ureaplasma parvum strain followed by (i) erythromycin treatment (intramuscularly, 30 mg/kg/day, n = 6) or (ii) saline (intramuscularly, n = 6) at 100 days gestation. Fetuses were then delivered surgically at 125 days gestation. Despite injecting the same inoculum into all the ewes, significant differences between amniotic fluid and chorioamnion ureaplasmas were detected following chronic intraamniotic infection. Numerous polymorphisms were observed in domain V of the 23S rRNA gene of ureaplasmas isolated from the chorioamnion (but not the amniotic fluid), resulting in a mosaiclike sequence. Chorioamnion isolates also harbored the macrolide resistance genes erm(B) and msr(D) and were associated with variable roxithromycin minimum inhibitory concentrations. Remarkably, this variability occurred independently of exposure of ureaplasmas to erythromycin, suggesting that low-level erythromycin exposure does not induce ureaplasmal macrolide resistance in utero. Rather, the significant differences observed between amniotic fluid and chorioamnion ureaplasmas suggest that different anatomical sites may select for ureaplasma subtypes within nonclonal, clinical strains. This may have implications for the treatment of intrauterine ureaplasma infections.
    View less >
    Journal Title
    Biology of Reproduction
    Volume
    90
    Issue
    2
    DOI
    https://doi.org/10.1095/biolreprod.113.113456
    Subject
    Biological Sciences not elsewhere classified
    Publication URI
    http://hdl.handle.net/10072/64154
    Collection
    • Journal articles

    Footer

    Social media

    • Facebook
    • Twitter
    • YouTube
    • Instagram
    • Linkedin
    First peoples of Australia
    • Aboriginal
    • Torres Strait Islander

    Disclaimer

    • Privacy policy
    • Copyright matters
    • CRICOS Provider - 00233E

    Tagline

    • Gold Coast
    • Logan
    • Brisbane
    • Australia