Metatranscriptome and Resistome of the Endodontic Microbiome
Ericka T Pinheiro1, Lamprini Karygianni2, George T M Candeiro3
1Department of Dentistry, School of Dentistry, University of São Paulo, São Paulo, Brazil; Clinic of Conservative and Preventive Dentistry, Center of Dental Medicine, University of Zurich, Zürich, Switzerland.
Journal of Endodontics
|May 8, 2024
Summary
This study used metatranscriptomics to analyze microbial activity and antimicrobial resistance in endodontic infections. Findings reveal key pathogens and widespread antibiotic resistance genes, highlighting potential virulence factors.
Area of Science:
- Microbiology
- Genomics
- Infectious Diseases
Background:
- Endodontic infections harbor complex microbial communities.
- Understanding microbial function and antibiotic resistance is crucial for effective treatment.
Purpose of the Study:
- To investigate microbial composition, functional profiles, and antimicrobial resistance (AMR) gene expression in endodontic infections using metatranscriptomics.
- To identify active pathogens and their potential virulence and AMR mechanisms.
Main Methods:
- Collected root canal samples from primary and persistent endodontic infections.
- Performed RNA sequencing and analyzed data using Kraken2 for taxonomy, UniProt for function, and CARD for AMR genes.
Main Results:
- Identified dominant bacterial phyla (Proteobacteria, Bacteroidetes, Firmicutes, Actinobacteria) and key anaerobic species.
- Detected high expression of moonlighting proteins involved in bacterial virulence.
- Found significant expression of tetracycline and lincosamide resistance genes, primarily via efflux and target alteration.
Conclusions:
- Metatranscriptomics successfully identified active endodontic pathogens.
- Revealed expression of virulence factors and a diverse array of antimicrobial resistance genes in endodontic infections.
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