AUTHOR=Wu Wenhao , Lu Lingling , Fan Wenjia , Chen Chun , Jin Dazhi , Pan Hongying , Li Xi 

TITLE=Complete Genome Sequences of Two Novel KPC-2-Producing IncU Multidrug-Resistant Plasmids From International High-Risk Clones of Escherichia coli in China

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.698478

DOI=10.3389/fmicb.2021.698478

ISSN=1664-302X

ABSTRACT=<p>The rapidly increasing prevalence of <italic>Klebsiella pneumoniae</italic> carbapenemase 2 (KPC-2)-producing bacteria has become a serious challenge to public health. Currently, the <italic>bla</italic><sub><italic>KPC–</italic></sub><sub>2</sub> gene is mainly disseminated through plasmids of different sizes and replicon types. However, the plasmids carrying the <italic>bla</italic><sub><italic>KPC–</italic></sub><sub>2</sub> gene have not been fully characterized. In this study, we report the complete genome sequences of two novel <italic>bla</italic><sub><italic>KPC–</italic></sub><sub>2</sub>-harboring incompatibility group U (IncU) plasmids, pEC2341-KPC and pEC2547-KPC, from international high-risk clones of <italic>Escherichia coli</italic> isolated from Zhejiang, China. Two KPC-2-producing <italic>E. coli</italic> isolates (EC2341 and EC2547) were collected from clinical samples. Whole-genome sequencing (WGS) analysis indicated that EC2341 and EC2547 belonged to the ST410 and ST131 clones, respectively. S1-nuclease pulsed-field gel electrophoresis (S1-PFGE), Southern blot and conjugation experiments confirmed the presence of the <italic>bla</italic><sub><italic>KPC–</italic></sub><sub>2</sub> gene on the pEC2341-KPC plasmid and that this was a conjugative plasmid, while the <italic>bla</italic><sub><italic>KPC–</italic></sub><sub>2</sub> gene on the pEC2547-KPC plasmid was a non-conjugative plasmid. In addition, plasmid analysis further revealed that the two <italic>bla</italic><sub><italic>KPC–</italic></sub><sub>2</sub>-harboring plasmids have a close evolutionary relationship. To the best of our knowledge, this is the first report of <italic>E. coli</italic> strains carrying the <italic>bla</italic><sub><italic>KPC–</italic></sub><sub>2</sub> gene on IncU plasmids. The emergence of the IncU-type <italic>bla</italic><sub><italic>KPC–</italic></sub><sub>2</sub>-positive plasmid highlights further dissemination of <italic>bla</italic><sub><italic>KPC–</italic></sub><sub>2</sub> in <italic>Enterobacteriaceae</italic>. Therefore, effective measures should be taken immediately to prevent the spread of these <italic>bla</italic><sub><italic>KPC–</italic></sub><sub>2</sub><sub>–</sub>positive plasmids.</p>