Characterization of Plasmids

  • Ioanna D. Dimopoulou
  • Mohd-Zain Zaini
  • Derrick W. Crook
Part of the Methods in Molecular Medicine™ book series (MIMM, volume 71)


Antibiotic resistant strains of Haemophilus influenzae appeared in the early 1970s and studies on these strains led to the detection of large 40–50 kb conjugative plasmids (1, 2, 3). Early work was hampered by the failure to easily detect extrachromosomal plasmid in clinical isolates. However, closed circular plasmid was readily detected in exconjugants following conjugal transfer of plasmid (4). Early, it was recognized that small, approx 5-kb, nonconjugative plasmid was associated with a proportion of strains exhibiting β-lactamasepositive ampicillin resistance (1,2). We concentrate here on characterization of large conjugative plasmids.


Haemophilus Influenzae Multilocus Sequence Typing Conjugal Transfer Primary Isolate Conjugative Plasmid 
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Copyright information

© Humana Press Inc. 2003

Authors and Affiliations

  • Ioanna D. Dimopoulou
    • 1
  • Mohd-Zain Zaini
    • 2
  • Derrick W. Crook
    • 2
  1. 1.Medical School of AlexandroupolisUniversity of ThraceAlexandroupolisGreece
  2. 2.Nuffield Department of Clinical Laboratory SciencesJohn Radcliffe HospitalOxfordUK

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