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Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
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Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes

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[Prevalence of AA(6')-APH(2")Ia gene among high-level aminoglycoside resistant Enterococci and Staphylococci]

Tomasz Jarzembowski1, Ewa Michnowska-Swincow, Katarzyna Wiśniewska

  • 1Katedra i Zakład Mikrobiologii Lekarskiej AM w Gdańsku.

Medycyna Doswiadczalna I Mikrobiologia
|April 24, 2004
PubMed

Insights

The AAC(6')-APH(2")Ia gene is not the sole cause of gentamycin resistance in Gram-positive cocci. This finding necessitates a re-evaluation of current aminoglycoside synergism prediction methods.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Context:

  • Aminoglycoside resistance in Gram-positive cocci is evolving.
  • The AAC(6 )-APH(2 )Ia gene is a known mechanism of gentamycin resistance.
  • Previous methods for predicting aminoglycoside synergism may require updates.

Purpose:

  • To investigate the prevalence of the AAC(6 )-APH(2 )Ia gene in gentamycin-resistant Gram-positive cocci from the Gdańsk region.
  • To assess the distribution of this resistance gene across different species, including Enterococcus faecalis, Staphylococcus haemolyticus, Staphylococcus aureus, and Staphylococcus epidermidis.

Summary:

  • The AAC(6 )-APH(2 )Ia gene was detected in 50-88% of gentamycin-resistant staphylococcal isolates (S. epidermidis, S. haemolyticus, MRSA).
  • In Enterococcus faecalis, the gene was found in 59% of gentamycin-resistant isolates.
  • The study suggests limited spread of this specific resistance gene among species, with higher prevalence in MRSA and S. haemolyticus.

Impact:

  • Findings indicate that the AAC(6 )-APH(2 )Ia gene is a significant, but not exclusive, contributor to gentamycin resistance in these bacteria.
  • The study highlights the need to consider alternative or additional resistance mechanisms when evaluating gentamycin treatment efficacy.
  • Results may inform revised clinical guidelines for predicting aminoglycoside synergism in Gram-positive bacterial infections.

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