Infection and Drug Resistance (Jan 2024)
Characterization of an NDM-1-Producing Citrobacter koseri Isolate from China
Abstract
Panpan Zi,1,* Ming Fang,2,* Hongfu Yang,1 Jiahao Zheng,3 Ning Ma,1 Qilong Liu1 1Department of Critical Care Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China; 2Institute for Infection Disease Control, Shandong Center for Disease Control and Prevention, Jinan, People’s Republic of China; 3Institute of Animal Quarantine, Chinese Academy of Inspection and Quarantine, Beijing, People’s Republic of China*These authors contributed equally to this workCorrespondence: Panpan Zi, Department of Critical Care Medicine, the First Affiliated Hospital of Zhengzhou University, No. 1 Longhu Zhonghuan Road, Jinshui District, Zhengzhou, Henan, People’s Republic of China, Tel +86-0371-66271356, Email [email protected]: The continuous rise in carbapenemase-producing Enterobacteriaceae infections is a major public health concern. However, there is limited information available on New Delhi metallo-β-lactamase-1 (NDM-1) producing Citrobacter koseri. In this study, we isolated a blaNDM-1-carrying C. koseri from a stool sample of an inpatient. Our aim was to investigate the phenotypic and genomic features of this clinically derived carbapenem-resistant C. koseri isolate and to characterize the transmission pattern of the IncFII/IncN plasmid that carries the blaNDM-1 gene.Methods and Results: S1-PFGE, Southern blot and conjugation assay confirmed the presence of blaNDM-1 gene in a conjugative plasmid. C. koseri L2395 and transconjugant L2395-EC600 strains showed similar resistance spectrum. Whole-genome analysis revealed that pL2395_NDM is an IncFII/IncN plasmid with a length of 67,839 bp. Moreover, blaNDM-1 gene was found encoded in the ISKpn19-blaNDM-1-ble-tnpF-dsbD-cutA-ISKpn19 cassette array. Phylogenetic analysis revealed that strain L2395 was close to an IMP-4-bearing C. koseri from Australia.Conclusion: Ongoing surveillance will be essential to control and prevent the spread of carbapenem-resistant Citrobacter spp. in the future.Keywords: Citrobacter koseri, carbapenem-resistant, NDM-1, whole-genome sequencing
