Multidrug-resistant monophasic Salmonella Typhimurium ST34 strain producing bla _NDM-5 carbapenemase isolated from a patient with rectal cancer in Hainan, China: comprehensive whole genome dissection of antibiotic resistance and virulence determinants.

Authors

Shan Zhong, Lei Xing, Licheng Wang, Chongzhen Wang, Xiaoying Fu, Lixia Xu, Yuanli Li, Huaxiong Zhu, Lvfen He, Xiong Zhu, Huan Li

Published in

Frontiers in cellular and infection microbiology. Volume 16. Pages 1942157. Epub Oct 16, 2026.

Abstract

Here, we report the identification and comprehensive whole-genome characterization of a New Delhi metallo-β-lactamase 5 (bla _NDM-5)-producing multidrug-resistant (MDR) monophasic Salmonella Typhimurium ST34 strain SYA001 from an immunocompromised rectal cancer patient. Monophasic Salmonella Typhimurium (Salmonella enterica subsp. enterica serovar 1,4,[5],12:i:-) is one of the leading causative agents of foodborne gastroenteritis and hospitalization worldwide, and the rapid emergence and spread of carbapenem-resistant strains have severely compromised clinical treatment and posed a major threat to public health.
In this study, a series of standardized phenotypic assays were performed to characterize the microbiological, biochemical, and antimicrobial resistance profiles of strain SYA001. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), biochemical identification, and slide agglutination serotyping were used for species and serotype confirmation. Antimicrobial susceptibility testing was conducted using the VITEK 2 compact system, and six types of carbapenemases were screened via a colloidal gold immunochromatographic assay. Whole-genome sequencing (WGS) was performed on the DNBSEQ-T7 platform, and a comprehensive bioinformatics pipeline was applied to dissect the genomic structure, phylogenetic characteristics, antibiotic resistance determinants, plasmid profiles, prophage regions, Salmonella pathogenicity islands (SPIs), and protein-protein interaction (PPI) network of the strain.
Our results confirmed that SYA001 is a serovar 1,4,[5],12:i:- monophasic Salmonella Typhimurium belonging to the globally epidemic ST34 clone. The strain exhibited an MDR phenotype, with resistance to 7 classes of antibiotics including carbapenems, cephalosporins, and aminoglycosides, and was only susceptible to aztreonam, amikacin, tigecycline, and colistin. Genomic analysis identified the core carbapenem resistance gene bla _NDM-5, along with multiple coexisting resistance genes including bla _OXA-10, qnrS1, tet(A), sul2, and sul3 and so on. Four plasmid replicons (IncHI2, IncHI2A, IncQ1, p0111), 15 prophage regions, and a complete set of virulence-related SPIs (SPI-1 to SPI-5,SPI-9, SPI-13, SPI-14) were detected. PPI network analysis revealed AcrA as the core hub of the efflux-mediated resistance regulatory network.
This study provides genomic insights into bla _NDM-5-producing MDR monophasic Salmonella. Typhimurium from an immunocompromised rectal cancer patient, supplements clinical surveillance data of carbapenem-resistant Salmonella in Hainan.

PMID:
42964160
Bibliographic data and abstract were imported from PubMed on 31 Oct 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.