Title of article :
Genomic Characterization of Multidrug-Resistant Carbapenemase-Producing Enterobacter cloacae ECL189, Co-producing KPC-2, NDM-1, TEM-1, TEM-95, and SHV-66
Author/Authors :
Du, Na Department of Clinical Laboratory - Yunnan University of Traditional Chinese Medicine, Kunming, China , Liu, Shumin Department of Clinical Laboratory - Kunming Medical University, Kunming , China , Yao, Jing Department of Clinical Laboratory - Kunming Medical University, Kunming , China , Yang, Kai Department of Clinical Laboratory - Kunming Medical University, Kunming , China , Lin, Yun Department of Clinical Laboratory - Yunnan University of Traditional Chinese Medicine, Kunming, China , Niu, Min Department of Clinical Laboratory - Kunming Medical University, Kunming , China , Zhang, Qingwen Department of Clinical Laboratory - Yunnan University of Traditional Chinese Medicine, Kunming, China , Yin, Zhiping Department of Clinical Laboratory - Yunnan University of Traditional Chinese Medicine, Kunming, China , Li, Huanqin Department of Clinical Laboratory - Kunming Medical University, Kunming , China , Du, Yan Department of Clinical Laboratory - Kunming Medical University, Kunming , China
Abstract :
Background: Carbapenem-resistant Enterobacteriaceae (CRE) has become a public health threat due to resistance to multiple antibiotics. The production of β-lactamase is the most important resistance mechanism of Enterobacteriaceae. Although isolates producing KPC-2 or NDM-1 enzymes have been reported widely, isolates co-producing KPC-2, NDM-1, TEM-1, TEM-95, SHV-66, and other β-lactamases have rarely been detected in the same strain, especially in Enterobacter cloacae.
Objectives: In this study, we identified and sequenced the genome of carbapenem-resistant E. cloacae ECL189 to in-depth analyze the resistance and transmission mechanisms of E. cloacae.
Methods: We investigated the antimicrobial susceptibility of ECL189 by a VITEK 2 system, E-test gradient strips, and K-B method. Whole-genome sequencing was used by the PacBio RS II platform and Illumina HiSeq 4000 platform. Antimicrobial resistance genes, virulence genes, non-coding RNA, and repeat sequences were predicted by biological information databases. A PCR was used to further confirm that the blaKPC-2, blaNDM-1, blaTEM-1, blaTEM-95, and blaSHV-66 genes existed in ECL189. A conjugation experiment was performed to determine the transferability of resistance. Molecular typing of ECL189 was done by multilocus sequence typing (MLST).
Results: Enterobacter cloacae ECL189 was resistant to 21 out of 23 tested antibiotics, but its transconjugant was resistant to 10 out of 18 tested antibiotics. The genome of ECL189 consisted of a 5,026,406 bp chromosome and four circular plasmids. In total, 26 resistance genes and 58 resistance proteins were identified. In addition, 77 determinants associated with bacterial virulence were identified. A large number of resistance and virulence genes were located in the plasmids. The results of whole-genome sequencing were consistent with the β-lactamase genes. The MLST analysis revealed that this strain belonged to ST74.
Conclusions: This study further revealed the resistance, virulence, and transmission mechanisms of carbapenem-resistant E. cloacae. Resistance and virulence genes spread in bacteria by the horizontal transfer of plasmids, which should attract more attention in relevant departments.
Keywords :
Enterobacter cloacae , Whole-Genome Sequencing , BlaKPC-2 , BlaNDM-1 , Carbapenems
Journal title :
Jundishapur Journal of Microbiology (JJM)
