Dissemination of blaNDM-5 Driven by Horizontal Transfer of IncFIA Plasmid Between Escherichia coli and Klebsiella pneumoniae Co-Isolated from a Patient’s Ascitic Fluid

Jing Yu,1,2 Yanzi Ding,1,2 Xue Zhang,1,2 Shuhong Tai,1,2 Chengwen Zhang,1,2 Cailin Liu,3 Enwu Yuan,1,2 Yitao Duan1,2 1Department of Laboratory Medicine, the Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, People’s Republic of China; 2Zhengzhou Key Laboratory for in vitro Diagnosis of Hypertensive Disorders of Pregnancy, Zhengzhou, Henan, 450052, People’s Republic of China; 3Department of Laboratory Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, People’s Republic of ChinaCorrespondence: Yitao Duan; Enwu Yuan, Department of Laboratory Medicine, the Third Affiliated Hospital of Zhengzhou University, No. 7 Front Kangfu Street, Zhengzhou, Henan, 450052, People’s Republic of China, Email [email protected]; [email protected]: Understanding the horizontal transfer of resistance genes, such as blaNDM-5, is pivotal in developing strategies to control the spread of resistance. In this study, we isolated two bacterial strains, Escherichia coli (designated GYB01) and Klebsiella pneumoniae (designated GYB02), from a single patient. The aim of our research is to explore the biological characteristics of these strains and to investigate the interspecies horizontal transfer of blaNDM-5.Materials and Methods: Strain identification and antimicrobial susceptibility testing were conducted using the Vitek 2 system. Both GYB01 and GYB02 were sequenced with the Illumina HiSeq platform. Bioinformatics analysis tools, including multilocus sequence typing, PlasmidFinder, ResFinder, and others, were utilized to analyze the strains. Additionally, conjugation assays and Galleria mellonella infection assays were employed to assess the strains.Results: The isolates exhibited similar antimicrobial resistance profiles and both harbored the blaNDM-5 gene within the IncFIA plasmids (pGYB01-2, 165.8 kb and pGYB02-2, 211.6 kb, respectively). These plasmids (pGYB01-2 and pGYB02-2) shared over 99% homology, suggesting a common ancestral origin. Conjugation experiments confirmed the transferability of the blaNDM-5 carrying IncFIA plasmids among Enterobacteriaceae. GYB02 possessed an iucACD-iutA gene cluster, exhibited high virulence, and tested positive in the string test.Conclusion: Our findings provide direct evidence of potential in vivo interspecies transfer of a multidrug-resistant plasmid, thus enriching our understanding of the mechanisms driving multidrug resistance (MDR) and aiding in the formulation of containment and treatment strategies.Keywords: CRE, NDM-5 carbapenemase, IncFIA plasmid, interspecies horizontal transfer