Complete sequence of broad-host-range plasmid pNOR-2000 harbouring the metallo-β-lactamase gene blaVIM-2 from Pseudomonas aeruginosa.

Objectives: Metallo-β-lactamases (MBLs) are increasingly reported not only in Enterobacteriaceae but also in Pseudomonas spp. These enzymes hydrolyse all β-lactams, including carbapenems, and are not inhibited by β-lactamase inhibitors. The aim of this study was to fully characterize a plasmid bearing the blaVIM-2 MBL gene identified in a Pseudomonas aeruginosa isolate.

Methods: This plasmid was fully sequenced by high-density pyrosequencing and annotated using the GenDB version 2.0 annotation tool. The evaluation of the broad-host-range replication of the pNOR-2000 replication initiation gene was assessed using electro-transformation and conjugation assays and the distribution of this replicase gene was evaluated using an international collection of VIM-producing Pseudomonas spp.

Results: Analysis of the 21 880 bp sequence of pNOR-2000 revealed a truncated and non-functional transfer operon, in addition to novel genes encoding a serine protease and toxin/antitoxin addiction systems. This broad-host-range plasmid shares high gene synteny with part of the mobile genomic island pKLC102 identified in P. aeruginosa strain C.

Conclusions: We report here the complete nucleotide sequence of plasmid pNOR-2000 from a P. aeruginosa clinical isolate harbouring the integron-located MBL gene blaVIM-2.