Molecular characterization of Enterotoxigenic Escherichia coli strains isolated from diarrheal patients in Korea during 2003-2011.
Enterotoxigenic Escherichia coli (ETEC) is one of the major causes of infectious diarrhea in developing countries. In order to characterize the molecular features of human ETEC isolates from Korea, we investigated the profiles of enterotoxin and colonization factor (CF) genes by polymerase chain reaction (PCR) and performed multilocus sequence typing (MLST) with a total of 291 ETEC strains. The specimens comprised 258 domestic strains isolated from patients who had diarrhea and were from widely separated geographic regions in Korea and 33 inflow strains isolated from travelers visiting other Asian countries. Heat-stable toxin (STh)-possessing ETEC strains were more frequent than heat-labile toxin (LT)-possessing ETEC strains in the domestic isolates, while the detection rates of both enterotoxin genes were similar in the inflow isolates. The profile of CF genes of domestic isolates was similar to that of inflow isolates and the major CF types of the strains were CS3-CS21-CS1/PCF071 and CS2-CS3-CS21. Most of these 2 CF types were detected in ETEC strains that possess both lt and sth genes. The major MLSTST types of domestic isolates were ST171 and ST955. Moreover, the 2 major CF types were usually found concomitantly with the 2 major MLST STs, ST171 and ST955. In conclusion, our genotyping results may provide useful information for guiding the development of geographically specific vaccines against human ETEC isolates.
Division of Enteric Bacterial Infections, Center for Infectious Diseases, Korea National Institute of Health, Osong-eup, Chungcheongbuk-do, Republic of Korea.
Kyung-Hwan
KH
Oh
Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan, Kyeonggi-do, Republic of Korea.
Dong Wook
DW
Kim
Division of Enteric Bacterial Infections, Center for Infectious Diseases, Korea National Institute of Health, Osong-eup, Chungcheongbuk-do, Republic of Korea.
Su-Mi
SM
Jung
Division of Enteric Bacterial Infections, Center for Infectious Diseases, Korea National Institute of Health, Osong-eup, Chungcheongbuk-do, Republic of Korea.
Seung-Hak
SH
Cho
D054307:Enterotoxigenic Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D005838:Genotype; D006801:Humans; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D056910:Republic of Korea
D029968:Escherichia coli Proteins