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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

[Study of macrolide, lincosamide, and streptogramin B antibiotics resistance in Staphylococcus aureus]

M Matsuoka1

  • 1Division of Microbiology, Hokkaido College of Pharmacy, Japan.

Yakugaku Zasshi : Journal of the Pharmaceutical Society of Japan
|April 25, 2000
PubMed

Insights

This study investigates macrolide antibiotic resistance in Staphylococcus aureus, identifying the msrSA gene region as crucial for inducible resistance. The findings reveal that this efflux pump mechanism, not target modification, is responsible for resistance to partial macrolide and streptogramin B antibiotics.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Biochemistry

Background:

  • Macrolide antibiotics inhibit bacterial protein synthesis by targeting 23S ribosomal RNA.
  • Antibiotic resistance mechanisms in staphylococci include target modification, drug inactivation, and active efflux.
  • Previous work indicated inducible resistance to partial macrolide and streptogramin B (PMS) antibiotics in Staphylococcus aureus.

Purpose of the Study:

  • To elucidate the genetic basis of inducible macrolide antibiotic resistance in Staphylococcus aureus.
  • To characterize the msrSA gene region involved in PMS resistance.
  • To investigate the relationship between PMS resistance and intracellular antibiotic accumulation.

Main Methods:

  • DNA sequencing of the msrSA region on various plasmids (constitutive resistant, inducible resistant, sensitive mutant).
  • Analysis of N-terminal amino acid sequences of membrane proteins in resistant strains.
  • Investigation of erythromycin accumulation in resistant and sensitive strains.

Main Results:

  • The msrSA gene region was sequenced, revealing its role in inducible PMS resistance.
  • A 63 kDa protein (MsrSA) associated with enhanced efflux of erythromycin was identified.
  • No evidence of target modification or drug inactivation was found; efflux appears to be the primary resistance mechanism.

Conclusions:

  • The msrSA gene and its regulatory region are essential for inducible resistance to PMS antibiotics in Staphylococcus aureus.
  • Active efflux, mediated by the MsrSA protein, is the primary mechanism of resistance.
  • Understanding these mechanisms is critical for developing strategies to combat antibiotic resistance.

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