[Source: PLoS One, full page: (LINK). Abstract, edited.]
OPEN ACCESS / PEER-REVIEWED / RESEARCH ARTICLE
Newly identified colistin resistance genes, mcr-4 and mcr-5, from upper and lower alimentary tract of pigs and poultry in China
Li Chen , Jilei Zhang , Jiawei Wang, Patrick Butaye, Patrick Kelly, Min Li, Feng Yang, Jiansen Gong, Afrah Kamal Yassin, Weina Guo, Jing Li, Chunlian Song, Chengming Wang
Published: March 14, 2018 / DOI: https://doi.org/10.1371/journal.pone.0193957
Antimicrobial resistance against colistin has emerged worldwide threatening the efficacy of one of the last-resort antimicrobials used for the treatment of Enterobacteriaceae. To investigate the presence of the recently identified colistin resistance genes (mcr-4, mcr-5) in China, we established PCRs to detect mcr-4 and mcr-5 on 213 anal and 1,339 nasal swabs from apparently healthy pigs (n = 1,454) in nine provinces, and 1,696 cloacal and 1,647 oropharyngeal samples from poultry (n = 1,836) at live-bird markets in 24 provinces of China. The prevalence of the mcr-4 in swine swabs (41.4%; 642/1,552) was significantly higher than in swabs from poultry (11.5%; 384/3,343). The mcr-4 gene was found in geese (49.5%, 54/109), chickens (17.2%, 257/1,498), pigeons (17.2%, 17/99) and ducks (15.4%, 20/130). In a similar trend, the prevalence of the mcr-5 in swine swabs (33.1%; 514/1552) was significantly higher than in swabs from poultry (5.6%; 187/3,343). The mcr-5 was identified in geese (17.4%, 19/109), chickens (9.9%, 148/1,498), ducks (7.7%, 10/130) and pigeons (3%, 3/99). The mcr-4 prevalence in the nasal swabs from pigs (59.2%, 58/98) was significantly higher than that in anal swabs (29.6%, 29/98) (P<0.001). Similarly, the mcr-5 prevalence in the nasal swabs from pigs (61.2%, 60/98) was significantly higher than in anal swabs (44.9%, 44/98) (P = 0.02), and significantly higher in oropharyngeal swabs (7.2%, 109/1,507) than in the cloacal swabs (3.7%, 56/1,507) (P<0.001). This study further confirms the presence of the mcr-4 and mcr-5 in animals and indicates these genes are prevalent and widespread in food producing animals (pig and poultry) in China. Future studies are needed to characterize the bacteria carrying the mcr-4 and mcr-5 and their locations on plasmids and/or the bacterial chromosomes, and determine co-resistances in the mcr-4 and mcr-5 positive strains.
Citation: Chen L, Zhang J, Wang J, Butaye P, Kelly P, Li M, et al. (2018) Newly identified colistin resistance genes, mcr-4 and mcr-5, from upper and lower alimentary tract of pigs and poultry in China. PLoS ONE 13(3): e0193957. https://doi.org/10.1371/journal.pone.0193957
Editor: Roman R. Ganta, Kansas State University, UNITED STATES
Received: January 1, 2018; Accepted: February 21, 2018; Published: March 14, 2018
Copyright: © 2018 Chen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All relevant data are within the paper and its Supporting Information files. All the nucleotide sequences were submitted to GenBank with accession numbers MG586909 to MG586912 for mcr-4 and MG586913 to MG586915 for mcr-5.
Funding: This work was supported by a grant from the National Key R & D Program of China (2016YFD0500804), a grant from the National Natural Science Foundation of China (NO: 31472225), the Priority Academic Program Development of Jiangsu Higher Education Institutions, and the Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
Keywords: Antibiotics; Drugs Resistance; Colistin; Pigs; Poultry; China; MCR4; MCR5.