Infection and Drug Resistance (Aug 2021)
Emergence and Genetic Characterization of Plasmid-Encoded VIM-2-Producing Pseudomonas stutzeri with Novel Integron In1998 Isolated from Cerebrospinal Fluid
Abstract
Shuxiu Liu,1,2 Hao Xu,2 Xiaobing Guo,1 Shuang Li,3 Qian Wang,1,2 Yuan Li,4 Ruishan Liu,1,2 Jianjun Gou1 1Department of Laboratory Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, People’s Republic of China; 2State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, People’s Republic of China; 3Department of Obstetrics and Gynecology, Zhengzhou Central Hospital Affiliated to Zhengzhou University, Zhengzhou, 450052, People’s Republic of China; 4Department of Nuclear Medicine, The First Affiliated Hospital of ZhengZhou University, Zhengzhou, 450052, People’s Republic of ChinaCorrespondence: Jianjun Gou Tel +86 371 6627 8237Fax +86 371 6691 3569Email [email protected]: To investigate the genomic and plasmid characteristics of a newly discovered Pseudomonas stutzeri strain with a blaVIM-2-carrying plasmid and novel integron In 1998 isolated from a cerebrospinal fluid specimen in a teaching hospital.Methods: Species identification was performed by MALDI-TOF MS, and blaVIM-2 was identified by PCR and Sanger sequencing. Whole-genome sequencing analysis was conducted using the Illumina NovaSeq 6000 and Oxford Nanopore platforms. Integron detection was performed using INTEGRALL. The phylogenetic tree was constructed by using kSNP3.0. Plasmid characteristics were assessed by S1-pulsed-field gel electrophoresis (S1-PFGE), Southern blotting, conjugation experiments, and whole-genome sequencing analysis. Comparative genomics analysis of the plasmid and genetic context of blaVIM-2 were conducted by using BLAST Ring Image Generator (BRIG) and Easyfig 2.3, respectively.Results: ZDHY95, an MDR strain of P. stutzeri harboring blaVIM-2, was identified. It was sensitive only to amikacin and was resistant to carbapenems, β-lactams, aztreonam, fluoroquinolones, and aminoglycosides. Joint S1-PFGE, Southern blot, conjugation assay, and whole-genome sequencing experiments confirmed that the blaVIM-2 gene was located within class I integron In 1722 of the plasmid and that the surrounding genetic environment was 5ʹCS-aacA4ʹ-30-blaVIM-2-aacA4ʹ-3ʹCS. The novel class I integron In 1998 was detected on the chromosome of P. stutzeri ZDHY95, and the gene cassette array was 5ʹCS-aacA3-aadA13-cmlA8-blaOXA-246-arr3-dfrA27-3ʹCS. Phylogenetic analysis showed that antimicrobial resistance gene-carrying P. stutzeri isolates were divided into two clusters, mainly containing isolates from the USA and Pakistan.Conclusion: A novel blaVIM-2-carrying conjugative plasmid, pZDHY95-VIM-2, was reported for the first time in P. stutzeri, elucidating the genetic environment and transfer mechanism. The gene structure of the novel class I integron In 1998 was also clarified. We explored the phylogenetic relationship of P. stutzeri with drug resistance genes and suggested that Pseudomonas with metallo-β-lactamases (MBLs) in the hospital environment may cause infection in patients with long-term intubation or after interventional surgery.Keywords: Pseudomonas stutzeri, blaVIM-2, In 1998, In 1722, Tn 5563, whole-genome sequencing, bacterial genomics, antibiotic resistance
