AUTHOR=Hu Xinjun , Yu Xiao , Shang Yibing , Xu Hao , Guo Lihua , Liang Yile , Kang Yixin , Song Li , Sun Jifeng , Yue Feng , Mao Yimin , Zheng Beiwen 

TITLE=Emergence and Characterization of a Novel IncP-6 Plasmid Harboring blaKPC–2 and qnrS2 Genes in Aeromonas taiwanensis Isolates

JOURNAL=Frontiers in Microbiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2019.02132

DOI=10.3389/fmicb.2019.02132

ISSN=1664-302X

ABSTRACT=<p>The dissemination of <italic>Klebsiella pneumoniae</italic> carbapenemases (KPCs) among Gram-negative bacteria is an important threat to global health. However, KPC-producing bacteria from environmental samples are rarely reported. This study aimed to elucidate the underlying resistance mechanisms of three carbapenem-resistant <italic>Aeromonas taiwanensis</italic> isolates recovered from river sediment samples. Pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS) analysis indicated a close evolutionary relationship among <italic>A. taiwanensis</italic> isolates. S1-PFGE, Southern blot and conjugation assays confirmed the presence of <italic>bla</italic><sub>KPC–</sub><sub>2</sub> and <italic>qnrS2</italic> genes on a non-conjugative plasmid in these isolates. Plasmid analysis further showed that pKPC-1713 is an IncP-6 plasmid with a length of 53,205 bp, which can be transformed into DH5α strain and mediated carbapenems and quinolones resistance. The plasmid backbone of p1713-KPC demonstrated 99% sequence identity to that of IncP-6-type plasmid pKPC-cd17 from <italic>Aeromonas</italic> spp. and IncP-6-type plasmid: 1 from <italic>Citrobacter freundii</italic> at 74% coverage. A 14,808 bp insertion sequence was observed between <italic>merT</italic> gene and hypothetical protein in p1713-KPC, which include the quinolone resistance <italic>qnrS2</italic> gene. Emergence of plasmid-borned <italic>bla</italic><sub>KPC</sub> and <italic>qnrS2</italic> genes from <italic>A. taiwanensis</italic> isolates highlights their possible dissemination into the environment. Therefore, potential detection of such plasmids from clinical isolates should be closely monitored.</p>