Staphylococcus efflux msr(A) gene characterized in Streptococcus, Enterococcus, Corynebacterium, and Pseudomonas
Kayode K Ojo1, Megan J Striplin, Catherine C Ulep
1Department of Pathobiology, Box 357238, University of Washington, Seattle, Washington 98195-7238, USA.
Antimicrobial Agents and Chemotherapy
|February 24, 2006
Abstract:
The staphylococcal msr(A) gene, coding for a macrolide efflux protein, was identified in three new gram-positive genera and one gram-negative genus. These msr(A) genes shared 99 to 100% identity with each other and the staphylococcal gene. This study demonstrates that the msr(A) gene has a wider host range than previously reported.
Insights
The staphylococcal msr(A) gene, which codes for macrolide efflux protein, was found in new bacterial genera. This indicates the macrolide efflux gene has a broader host range than previously understood.
Area of Science:
- Microbiology
- Genetics
- Molecular Biology
Background:
- The msr(A) gene in Staphylococcus encodes a macrolide efflux protein, conferring resistance to macrolide antibiotics.
- Understanding the distribution of antibiotic resistance genes is crucial for combating antimicrobial resistance.
Purpose of the Study:
- To investigate the presence and genetic relatedness of the msr(A) gene in bacterial genera beyond Staphylococcus.
- To determine the host range of the msr(A) macrolide efflux gene.
Main Methods:
- Bacterial DNA isolation and sequencing.
- Comparative sequence analysis of the msr(A) gene.
Main Results:
- The msr(A) gene was identified in three novel gram-positive bacterial genera and one gram-negative genus.
- The identified msr(A) genes exhibited high sequence identity (99-100%) to the staphylococcal msr(A) gene.
Conclusions:
- The msr(A) gene is not exclusive to Staphylococcus and has a wider host range than previously recognized.
- The broad dissemination of the msr(A) gene suggests potential for widespread macrolide resistance in diverse bacterial populations.
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