Classification of perA sequences and their correlation with autoaggregation in typical enteropathogenic Escherichia coli isolates collected in Japan and Thailand
Version of Record online: 25 FEB 2010
© 2010 The Societies and Blackwell Publishing Asia Pty Ltd
Microbiology and Immunology
Volume 54, Issue 4, pages 184–195, April 2010
How to Cite
Iida, M., Okamura, N., Yamazaki, M., Yatsuyanagi, J., Kurazono, T., Suzuki, R., Hiruta, N., Isobe, J., Seto, K., Kawano, K., Narimatsu, H., Ratchtrachenchai, O.-A., Okabe, N. and Ito, K. (2010), Classification of perA sequences and their correlation with autoaggregation in typical enteropathogenic Escherichia coli isolates collected in Japan and Thailand. Microbiology and Immunology, 54: 184–195. doi: 10.1111/j.1348-0421.2010.00212.x
- Issue online: 5 APR 2010
- Version of Record online: 25 FEB 2010
- Received 28 September 2009; revised 12 Janunary 2010; accepted 19 Janunary 2010.
- bundle forming pilus;
- enteropathogenic Escherichia coli;
Enteropathogenic Escherichia coli (EPEC) strains produce a bundle-forming pilus (BFP) that mediates localized adherence (LA) to intestinal epithelial cells. The major structural subunit of the BFP is bundlin, which is encoded by the bfpA gene located on a large EAF plasmid. The perA gene has been shown to activate genes within the bfp operon. We analyzed perA gene polymorphism among typical (eae- and bfpA- positive) EPEC strains isolated from healthy and diarrheal persons in Japan (n= 27) and Thailand (n= 26) during the period 1995 to 2007 and compared this with virulence and phenotypic characteristics. Eight genotypes of perA were identified by heteroduplex mobility assay (HMA). The strains isolated in Thailand showed strong autoaggregation and had an intact perA, while most of those isolated in Japan showed weak or no autoaggregation, and had a truncated perA due to frameshift mutation. The degree of autoaggregation was well correlated with adherence to HEp-2 cells, contact hemolysis and BFP expression. Our results showed that functional deficiency due to frameshift mutation and subsequent nonsense mutation in perA reduced BFP expression in typical EPEC strains isolated in Japan.