Genomic insights into the tmexCD-toprJ: plasmid-mediated evolution, dissemination and diversity in bacterial populations - PubMed
7 hours ago
- #Antimicrobial Resistance
- #Plasmid Diversity
- #Genomic Surveillance
- The study focuses on the plasmid-mediated tigecycline resistance gene tmexCD-toprJ, its spread, and plasmid adaptation mechanisms.
- Analysis of 197 tmexCD-toprJ-carrying plasmids revealed significant genetic diversity, clustering into 18 groups and 12 singletons.
- Predominant host species include Klebsiella pneumoniae (53.3%), Pseudomonas aeruginosa (16.8%), and Klebsiella quasipneumoniae (4.1%).
- MOB-suite typing classified 53.8% of plasmids as conjugative, 5.6% as mobilizable, and 40.61% as non-mobilizable.
- The MOBH family was predicted in over half of the tmexCD-toprJ-carrying plasmids.
- Main variants identified were tmexCD1-toprJ1, tmexCD2-toprJ2, and tmexCD3-toprJ1, each associated with different plasmid types.
- 14 plasmids co-localized tmexCD-toprJ with carbapenemase (blaNDM/KPC) and mcr genes, forming high-risk resistance platforms.
- A notable 36,483 bp insertion in IncP/rep_cluster_1115 plasmids disrupted tmexC6D6-toprJ1b and included heavy metal resistance genes.
- The study underscores the urgent need for enhanced surveillance due to the convergence of resistance genes in clinically prevalent plasmids.