Background: Salmonella enterica serovar Typhimurium is the most important serovar associated with human salmonellosis worldwide. Here we aimed to explore the molecular epidemiology and genetic characteristics of this serovar in Guangdong, China.

Methodology: We evaluated the molecular epidemiology and genetic characteristics of 294 endemic Salmonella Typhimurium clinical isolates which were collected from 1977 to 2011 in Guangdong, China, and compared them with a global set of isolates of this serovar using epidemiological data and Multilocus Sequence Typing (MLST) analysis.

Principal Finding: The 294 isolates were assigned to 13 Sequencing types (STs) by MLST, of which ST34 and ST19 were the most common in Guangdong. All the STs were further assigned to two eBurst Groups, eBG1 and eBG138. The eBG1 was the major group endemic in Guangdong. Nucleotide and amino acid variability were comparable for all seven MLST loci. Tajima's D test suggested positive selection in hisD and thrA genes (p<0.01), but positive selection was rejected for the five other genes (p>0.05). In addition, The Tajima's D test within each eBG using the global set of isolates showed positive selection in eBG1 and eBG138 (p<0.05), but was rejected in eBG243 (p>0.05). We also analyzed the phylogenetic structure of Salmonella Typhimurium from worldwide sources and found that certain STs are geographically restricted. ACSSuT was the predominant multidrug resistance pattern for this serovar. The resistant profiles ACSSuTTmNaG, ACSSuTTmNa and ACSuTTmNaG seem to be specific for ST34, and ASSuTNa for ST19.

Conclusion: Here we presented a genotypic characterization of Salmonella Typhimurium isolates using MLST and found two major STs are endemic in Guangdong. Our analyses indicate that genetic selection may have shaped the Salmonella Typhimurium populations. However, further evaluation with additional isolates from various sources will be essential to reveal the scope of the epidemiological characteristics of Salmonella Typhimurium in Guangdong, China.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4224511PMC
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0113145PLOS

Publication Analysis

Top Keywords

salmonella typhimurium
24
guangdong china
12
epidemiological characteristics
8
typhimurium guangdong
8
molecular epidemiology
8
epidemiology genetic
8
genetic characteristics
8
global set
8
set isolates
8
ebg1 ebg138
8

Similar Publications

Unlabelled: are Gram-negative, rod-shaped, entero-invasive foodborne bacteria and are frequently detected in chicken houses and facilities of poultry broiler complexes. The objective of this study was to determine the prevalence, critical entry points, and movement pattern of along different stages of a complex. A total of 1,071 environmental samples were collected from 38 production houses (8 pullet, 10 breeder, and 20 broiler), a hatchery, 6 transport trucks, and a processing plant.

View Article and Find Full Text PDF

Studying the molecular basis of intestinal infections caused by enteric pathogens at the tissue level is challenging, because most human intestinal infection models have limitations, and results obtained from animals may not reflect the human situation. Infections with Salmonella enterica serovar Typhimurium (STm) have different outcomes between organisms. 3D tissue modeling of primary human material provides alternatives to animal experimentation, but epithelial co-culture with immune cells remains difficult.

View Article and Find Full Text PDF

Development of a bacteria-nanosapper for the active delivery of ZIF-8 particles containing therapeutic genes for cancer immune therapy.

Acta Pharm Sin B

December 2024

School of Pharmacy, Institute of Hepatology and Metabolic Diseases, Department of Hepatology, the Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Hangzhou 311121, China.

Specific tumor-targeted gene delivery remains an unsolved therapeutic issue due to aberrant vascularization in tumor microenvironment (TME). Some bacteria exhibit spontaneous chemotaxis toward the anaerobic and immune-suppressive TME, which makes them ideal natural vehicles for cancer gene therapy. Here, we conjugated ZIF-8 metal-organic frameworks encapsulating eukaryotic murine interleukin 2 () expression plasmid onto the surface of VNP20009, an attenuated strain with well-documented anti-cancer activity, and constructed a TME-targeted delivery system named /ZIF-8@.

View Article and Find Full Text PDF

infections pose significant public health challenges worldwide. The diversity of strains, particularly those isolated from environmental and clinical sources, necessitates innovative approaches to prevention and treatment. Previous research has shown that small extracellular vesicles (sEVs) produced by macrophages during Typhimurium infection can induce robust immune responses when used as a vaccine, offering complete protection in systemic infection models.

View Article and Find Full Text PDF

Assessing the impact of different solvents in the bacterial reverse mutation test.

Environ Mol Mutagen

January 2025

Department of Pharmacology and Toxicology, Zydus Research Centre, Zydus Lifesciences Limited, Ahmedabad, Gujarat, India.

The bacterial reverse mutation test is essential for identifying the mutagenic potential of chemicals. The solubility of the test substance is vital for achieving the recommended assay concentration. Preferred solvents like dimethyl sulfoxide and water are chosen for their compatibility and historical data.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!