Infection and Drug Resistance (May 2024)
Genomic Insights into the First Emergence of blaNDM-5-Carrying Carbapenem-Resistant Salmonella enterica Serovar London Strain in China
Abstract
Shaohua Tan,1,* Xiangchen Li,2,* Bing Lu,1,3 Yibin Lin,3 Yunxiang Cai,1 Jie He,4 Sisi Chen,2 Junli Gao,2 Junshun Gao,2 Xinhua Qiang1 1Department of Clinical Laboratory, The First People’s Hospital of Huzhou, Huzhou, Zhejiang, 313000, People’s Republic of China; 2Key Laboratory of Precision Medicine in Diagnosis and Monitoring Research of Zhejiang Province, Hangzhou, Zhejiang, 310020, People’s Republic of China; 3School of Medicine, Huzhou University, Huzhou, Zhejiang, 313000, People’s Republic of China; 4Department of Infectious Diseases, The First People’s Hospital of Huzhou, Huzhou, Zhejiang, 313000, People’s Republic of China*These authors contributed equally to this workCorrespondence: Xinhua Qiang, Department of Clinical Laboratory, The First People’s Hospital of Huzhou, No. 158 Back Square Road, Wuxing District, Huzhou, Zhejiang, 313000, People’s Republic of China, Email [email protected]: Carbapenem-resistant Salmonella enterica (S. enterica) pose a significant threat to public health, causing gastroenteritis and invasive infections. We report the first emergence of a carbapenem-resistant S. enterica serovar London strain, A132, carrying the blaNDM-5 gene in China. Whole-genome sequencing and bioinformatics analysis assigned A132 to be ST155, a multidrug-resistant clone frequently reported in China. The strain A132 exhibited resistance to multiple antibiotics, with 20 acquired antibiotic resistance genes (ARGs) identified, predominantly located on the IncFIB plasmid (pA132-1-NDM). Notably, the blaNDM-5 gene was located within an IS 26 flanked-class 1 integron-ISCR1 complex, comprising two genetic cassettes. One cassette is the class 1 integron, which may facilitate the transmission of the entire complex, while the other is the blaNDM-5-containing ISCR1-IS 26-flanked cassette, carrying multiple other ARGs. Genbank database search based on the blaNDM-5-carrying cassette identified a similar genetic context found in transmissible IncFIA plasmids from Escherichia coli (p91) and Enterobacter hormaechei (p388) with a shared host range, suggesting the potential for cross-species transmission of blaNDM-5. To our knowledge, this is the first reported case of Salmonella serovar London ST155 harboring blaNDM-5 gene. Phylogenetic analysis indicated a close relationship between A132 and eight S. London ST155 strains isolated from the same province. However, A132 differed by carrying the blaNDM-5 gene and four unique ARGs. Given the high transmissibility of the F-type plasmid harboring blaNDM-5 and 18 other ARGs, it is imperative to implement vigilant surveillance and adopt appropriate infection control measures to mitigate the threat to public health.Keywords: blaNDM-5, Salmonella London, ST155, carbapenem resistance, IncFIB, integron
