Dataset Information

The molecular epidemiological characteristics and genetic diversity of salmonella typhimurium in Guangdong, China, 2007-2011.

ABSTRACT:

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.

SUBMITTER: Sun J

PROVIDER: S-EPMC4224511 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The molecular epidemiological characteristics and genetic diversity of salmonella typhimurium in Guangdong, China, 2007-2011.

Sun Jiufeng J Ke Bixia B Huang Yanhui Y He Dongmei D Li Xiaocui X Liang Zhaoming Z Ke Changwen C

PloS one 20141107 11

<h4>Background</h4>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.<h4>Methodology</h4>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 isola ...[more]

PMID: 25380053

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Dataset Information

The molecular epidemiological characteristics and genetic diversity of salmonella typhimurium in Guangdong, China, 2007-2011.

Background

Methodology

Principal finding

Conclusion

Publications

The molecular epidemiological characteristics and genetic diversity of salmonella typhimurium in Guangdong, China, 2007-2011.

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