Molecular Detection of blaTEM and blaSHV Genes in ESBL-Producing Acinetobacter baumannii Isolated from Antarctic Soil

Clara Pazos1, Miguel Gualoto2, Tania Oña1

  • 1Grupo de Investigaciones Antárticas (GIAN), Universidad Técnica del Norte (UTN), Av. 17 de Julio 5-21 y Gral. José María Córdova, Ibarra 100150, Ecuador.

Microorganisms
|March 27, 2025
PubMed

Insights

Antimicrobial resistance (AMR) genes, including blaTEM and blaSHV, were found in Acinetobacter bacteria from Antarctic soil. This shows AMR exists even in pristine, cold environments, not just human-impacted areas.

Area of Science:

  • Microbiology
  • Environmental Science
  • Molecular Biology

Background:

  • Antimicrobial resistance (AMR) is a growing global health concern.
  • Pristine ecosystems were previously assumed to lack clinically significant resistance genes.
  • The presence of AMR in extreme cold environments like Antarctica challenges this assumption.

Purpose of the Study:

  • To investigate the molecular basis of AMR in Acinetobacter spp. from Antarctic soil.
  • To identify specific resistance genes, particularly blaTEM and blaSHV, associated with extended-spectrum beta-lactamase (ESBL) production.
  • To understand the implications of AMR in remote ecosystems for global resistance patterns.

Main Methods:

  • Isolation and microbiological identification of Antarctic soil bacteria.
  • Molecular detection of bacterial species using 16S rRNA/rpoB genes via polymerase chain reaction (PCR).
  • Identification of 10 different beta-lactamase-producing genes using PCR and subsequent sequencing of amplicons.

Main Results:

  • Acinetobacter baumannii was identified as a key species present in the soil samples.
  • Both blaTEM and blaSHV genes, responsible for resistance to penicillins and cephalosporins, were detected.
  • Sequence analysis revealed conserved antimicrobial resistance genes (ARGs), suggesting stability and potential for horizontal gene transfer.

Conclusions:

  • Antimicrobial resistance determinants are present in bacteria inhabiting extreme cold environments.
  • AMR is not limited to human-impacted areas and can persist in remote natural reservoirs.
  • Findings highlight the need to consider environmental reservoirs in strategies to mitigate the global spread of AMR.