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Antiplasmid effect of promethazine in mixed bacterial cultures

Annamária Molnár1, Leonard Amaral, Joseph Molnár

  • 1Department of Medical Microbiology, University of Szeged, Dóm tér 10, H-6720 Szeged, Hungary. molnarj@comser.szote.u-szeged.hu

International Journal of Antimicrobial Agents
|September 19, 2003
PubMed

Insights

Promethazine effectively eliminates plasmids in single bacterial species. In mixed cultures, bacterial interactions and higher temperatures enhance promethazine

Area of Science:

  • Microbiology
  • Bacteriology
  • Antimicrobial Agents

Background:

  • Promethazine is a known antiplasmid agent effective against single bacterial species like Escherichia coli.
  • The impact of mixed microbial communities on promethazine's efficacy remains less understood.

Purpose of the Study:

  • To investigate how a heterogeneous microbial flora influences plasmid elimination by promethazine.
  • To model mixed bacterial infections and assess promethazine's antiplasmid activity in such environments.

Main Methods:

  • Studied F'lac plasmid elimination in E. coli K12 LE140 within mixed cultures.
  • Utilized numerically predominant Gram-positive species (Bacillus cereus, Staphylococcus epidermidis).
  • Assessed promethazine concentrations (0-120 mg/l) at varying temperatures (23, 37, 39°C).

Main Results:

  • Bacterial-bacterial interactions within mixed cultures modified individual species' growth rates.
  • Certain interactions, particularly with Staphylococcus epidermidis, increased promethazine-induced plasmid curing frequency.
  • Promethazine demonstrated enhanced plasmid elimination efficacy at elevated temperatures.

Conclusions:

  • Microbial community composition significantly impacts promethazine's antiplasmid activity.
  • Temperature is a critical factor influencing promethazine's effectiveness in plasmid elimination.
  • Findings suggest promethazine's potential in managing infections with complex bacterial flora.

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