Back to Journals » Infection and Drug Resistance » Volume 13

An NDM-1-Producing Acinetobacter towneri Isolate from Hospital Sewage in China

Authors Wang K, Li P, Li J, Hu X, Lin Y, Yang L, Qiu S, Ma H, Li P, Song H

Received 20 January 2020

Accepted for publication 26 March 2020

Published 16 April 2020 Volume 2020:13 Pages 1105—1110


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 2

Editor who approved publication: Dr Joachim Wink

Kaiying Wang,1,2,* Peihan Li,1,2,* Jinhui Li,2,* Xiaofeng Hu,2,* Yanfeng Lin,1,2 Lang Yang,1,2 Shaofu Qiu,2 Hui Ma,*,3 Peng Li,2 Hongbin Song2

1College of Military Medicine, Academy of Military Sciences, Beijing, People’s Republic of China; 2Center for Disease Control and Prevention of PLA, Beijing, People’s Republic of China; 3The Sixth Medical Center of PLA General Hospital, Beijing, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Peng Li; Hongbin Song Tel/ Fax +86-10-66948475

Background: The New Delhi metallo-β-lactamase-1 (NDM-1)-positive plasmid and its variants pose daunting threats to public health. Hospital sewage was considered as an important reservoir of antibiotic genes. Numerous and diverse taxa of multidrug-resistant (MDR) bacteria carrying NDM-1-positive plasmids have been identified during routine surveillance of hospital sewage. We herein report a carbapenem-resistant Acinetobacter towneri strain AeBJ009 with an NDM-1-positive plasmid isolated from hospital sewage.
Materials and Methods: Bacteria were isolated from cultures of hospital sewage and identified by using the Vitek 2 compact system and 16S rRNA sequencing. The blaNDM-1 gene was amplified and confirmed by sequencing. Antimicrobial susceptibility testing was performed using AST-GN14 on the Vitek2 compact system. In addition, the blaNDM-1 gene was located by Southern blotting. Conjugation experiment and whole-genome sequencing were performed for further analysis.
Results: Strain AeBJ009 was isolated from hospital sewage and identified as A. towneri. Antimicrobial susceptibility testing revealed an MDR phenotype. Pulsed-field gel electrophoresis and Southern blotting showed that strain AeBJ009 carries three plasmids and that blaNDM-1 is located on the 47kb plasmid pNDM-AeBJ009. However, the conjugation experiment to transfer pNDM-AeBJ009 to Escherichia coli strain J53 was unsuccessful. Whole-genome sequencing found that pNDM-AeBJ009 contains a Tn 125 element carrying blaNDM-1. The ble gene downstream of blaNDM-1 displayed a single-nucleotide polymorphism compared to its homologue on plasmid pM131_NDM1. BLAST analysis using the Comprehensive Antibiotic Resistance Database identified no gene polymorphisms with 100% identity to our ble variant.
Conclusion: The A. towneri strain AeBJ009 exhibiting an extended spectrum of antibiotic resistance was isolated from hospital sewage and may potentially exacerbate the risk of MDR bacterial infections. The prevention of nosocomial infections due to drug-resistant bacteria will require enhanced monitoring and control of MDR pathogens in environmental reservoirs.

Keywords: NDM-1, ble, Acinetobacter towneri, drug resistance

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]