Development of a serogroup-specific multiplex PCR assay to detect a set of Escherichia coli serogroups based on the identification of their O-antigen gene clusters.
The Escherichia coli serogroups O115, O126, O137, O158, O165, and O173 are pathogenic strains associated with diarrhea. Molecular approaches such as PCR have been proven to be rapid, inexpensive, and accurate. The sequences of the O-antigen-processing genes wzx and wzy are specific for different O antigens and are generally used as the target genes for the detection and identification of E. coli strains belonging to different O serogroups. In this report, the O-antigen gene clusters of these 6 O serogroups were sequenced, and genes were identified on the basis of homology. By screening these sequences against all 186 E. coli and Shigella strains, we found that the sequences of the wzx and wzy genes were serogroup-specific, and 2 specific primer pairs for each serogroup were screened out. A multiplex PCR assay targeting all 6 serogroups was developed. Twenty-nine strains were used to validate the specificity of the assay. The detection sensitivity was 1ng genomic DNA. As the assay was shown to be accurate and sensitive, it can be used for the identification and detection of strains belonging to these serogroups in stool and other environmental samples after being isolated by culture.
Wang
Quan
Q
TEDA School of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin 300457, China.
Ruan
Xiaojuan
X
Wei
Dongmei
D
Hu
Zhidong
Z
Wu
Lixia
L
Yu
Ting
T
Feng
Lu
L
Wang
Lei
L
D017931:DNA Primers; D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D016695:Glycosyltransferases / Q000235:genetics / Q000378:metabolism; D006801:Humans; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D005810:Multigene Family; D019081:O Antigens / Q000096:biosynthesis*; D016133:Polymerase Chain Reaction / Q000379:methods*; D015203:Reproducibility of Results; D012703:Serotyping; D013045:Species Specificity
D017931:DNA Primers; D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; D019081:O Antigens; C543926:Wzx protein, E coli; D016695:Glycosyltransferases; C513753:Wzy polymerase, E coli