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Published on: September 5, 2013
Phim46.1, the main Streptococcus pyogenes element carrying mef(A) and tet(O) genes
Andrea Brenciani1, Alessandro Bacciaglia, Carla Vignaroli
1Department of Biomedical Sciences, Section of Microbiology, Polytechnic University of Marche, Via Tronto 10/A, Ancona 60020, Italy.
Antimicrobial Agents and Chemotherapy
|October 28, 2009
Summary
Phim46.1, a mobile genetic element in Streptococcus pyogenes, carries erythromycin and tetracycline resistance genes. Its characterization reveals a unique structure and integration site, impacting antibiotic resistance dissemination.
Area of Science:
- Microbiology
- Genetics
- Molecular Biology
Background:
- Phim46.1 is a prevalent mobile genetic element in Streptococcus pyogenes.
- It carries mef(A) and tet(O) genes conferring resistance to erythromycin and tetracycline, respectively.
- Understanding its structure and behavior is crucial for antibiotic resistance research.
Purpose of the Study:
- To fully characterize the Phim46.1 prophage.
- To elucidate its genome organization, integration site, and relationship with other phages.
- To understand the genetic context of antibiotic resistance genes mef(A) and tet(O).
Main Methods:
- Genome sequencing of Phim46.1 (55,172 bp).
- Electron microscopy of induced phage particles.
- BLASTP analysis for protein sequence similarity.
- Analysis of phage DNA integration and excision.
Main Results:
- Phim46.1 exhibits a modular organization typical of tailed bacteriophages (Siphoviridae family).
- Integration occurred within a 23S rRNA uracil methyltransferase gene.
- The lysogeny module was disrupted by insertion of tet(O) and mef(A) genes.
- Phage DNA exists as both prophage and free circular DNA.
Conclusions:
- Phim46.1 is a well-characterized Siphoviridae family phage.
- Its genome structure facilitates the acquisition and dissemination of antibiotic resistance genes.
- The split lysogeny module and gene insertion provide insights into mobile genetic element evolution.
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