Transfer Dynamics of Extracellular Antibiotic Resistance Genes in Wastewater Treatment Plants

Strategic Insights -

Researchers have made new discoveries in the field of Science, as reported by a study conducted by Tsinghua University in Beijing, People's Republic of China. The study focused on the occurrence, transfer contribution, and potential hosts of intracellular and extracellular antibiotic resistance genes (ARGs) in an antibiotic and a municipal wastewater treatment plant (WTP). The findings suggest that free-extracellular ARGs were dominant in effluents, while the transformation frequency of eARGs mediated by plasmid RP4 in wastewater community was lower than the conjugation frequency of intracellular ARGs. This indicates that extracellular ARGs play a significant role in the spread of antibiotic resistance in WTPs.

Key Takeaways:

  • The study found that free-extracellular ARGs were dominant in effluents, with a range of 59.4-79.2%.
  • The transformation frequency of eARGs mediated by plasmid RP4 in wastewater community was 4.2-4.7 orders of magnitude lower than the conjugation frequency of intracellular ARGs.
  • This suggests that extracellular ARGs have lower transmission risks compared to intracellular ARGs.
  • A wide range of potential eARG hosts was identified, including some potential pathogens such as Pseudomonas and Acinetobacter.
  • The study concluded that extracellular ARGs play a significant role in the spread of antibiotic resistance in WTPs, especially in antibiotic WTPs.

Statistics:

  • 59.4-79.2% of free-extracellular ARGs were found in effluents.
  • The transformation frequency of eARGs mediated by plasmid RP4 in wastewater community was 4.2-4.7 orders of magnitude lower than the conjugation frequency of intracellular ARGs.
  • The study found that carbon-based additives accelerated the transformation dynamics of eARGs by 2.1-14.3-fold.
  • The study suggests that antibiotic wastewater can accelerate the transformation dynamics of eARGs by 2.1-14.3-fold even after the treatment process.

Sources:

  • "Transfer dynamics of extracellular antibiotic resistance genes during antibiotic and municipal wastewater treatment: contribution analysis and host identification." Bioresource Technology, 2025:133059.
  • Elsevier Sci Ltd, 125 London Wall, London, England (publisher of Bioresource Technology).