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Methodology for the Study of Horizontal Gene Transfer in Staphylococcus aureus
10:39

Methodology for the Study of Horizontal Gene Transfer in Staphylococcus aureus

Published on: March 10, 2017

Intraspecies transfer of a chloramphenicol-resistance plasmid of staphylococcal origin

Mausumi Bhakta1, Suranjana Arora, Manjusri Bal

  • 1Section of Microbiology, Department of Physiology, University College of Science & Technology University of Calcutta, Kolkata, India.

The Indian Journal of Medical Research
|November 8, 2003
PubMed
Abstract

Insights

A chloramphenicol resistance plasmid (pMC524/MBM) from Staphylococcus aureus was successfully transferred between clinical strains. This R-plasmid can replicate and express chloramphenicol resistance in new hosts, potentially driving resistance spread.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Background:

  • Antibiotic resistance in bacteria is a major clinical and pharmaceutical challenge.
  • Genetic exchange of R-plasmids contributes to the evolution of antibiotic resistance.
  • Staphylococcus aureus is a clinically significant pathogen known for multi-drug resistance.

Purpose of the Study:

  • To investigate the intraspecies transfer of a chloramphenicol resistance plasmid (pMC524/MBM) among clinical isolates of Staphylococcus aureus.
  • To determine the stability and expression of the transferred plasmid in recipient strains.

Main Methods:

  • Isolation of a chloramphenicol resistance plasmid (pMC524/MBM) from a multi-drug resistant S. aureus strain.
  • Plasmid preparation using lysostaphin and sucrose-mediated detergent lysis.
  • Analysis via agarose gel electrophoresis, transformation, Southern blotting, hybridization, and restriction endonuclease digestion.

Main Results:

  • The pMC524/MBM plasmid, conferring chloramphenicol resistance, was successfully transferred to chloramphenicol-sensitive S. aureus clinical strains.
  • Transformed strains contained plasmids identical in size and restriction digestion patterns to the original pMC524/MBM.

Conclusions:

  • The pMC524/MBM plasmid can transfer, replicate, and express chloramphenicol resistance in diverse clinical S. aureus strains without modification.
  • This R-plasmid may play a significant role in the dissemination of chloramphenicol resistance within S. aureus populations.

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