Characterization of a mobilizable megaplasmid carrying multiple resistance genes from a clinical isolate of Pseudomonas aeruginosa

• DOI: 10.3389/fmicb.2023.1293443
• Publication Date: 2023-11-27T06:42:00Z
• Authors: Li Mei; Yang Song; Dongxin Liu; Yixiao Li; Li Liu; Keyi Yu; Mengnan Jiang; Duochun Wang; Qiang Wei
• Keywords: Horizontal Gene Transfer; Insertion sequence

Introduction The horizontal transfer of antibiotic resistance genes mediated by plasmids seriously hinders the effectiveness modern medical treatment, and thus has attracted widespread attention. Additionally, co-selection mechanism (ARGs) heavy metal (MRGs) on mobile elements may further exacerbate genes. Methods In this study, a multidrug-resistant Pseudomonas aeruginosa strain, termed BJ86 (CHPC/NPRC1.4142), was isolated from patient's sputum specimen. vitro tests for antimicrobial susceptibility, conjugation, whole-genome sequencing, bioinformatics analysis were used to explore potential mechanisms its spread. Results discussion Sequencing indicates that P. carries an amazing 522.5 kb-length megaplasmid, pBJ86, which contained 93.5 multiple region (MRR); 18 kinds identified as ARGs in region, including tmexCD-oprJ , bla DIM−1 qnrVC6 mediate antibiotics operons mer mediates mercury resistance. addition, there is also 80 kb variable (VR) plasmid encoding relaxase type IV coupling protein (T4CP) determined both are related conjugation ability plasmid. Bioinformatics shows many functional have insertion sequences transposases their flanks, accumulated pBJ86 after acquisition events. Conjugated susceptibility verified mobility pBJ86-mediated To our knowledge, we first report mobilizable megaplasmid simultaneously carried can be transferred with frequencies 6.24 × 10 −7 transconjugants per donor cell.