TY - JOUR
T1 - Characterization of typical and atypical enteroaggregative escherichia coli in kagoshima, Japan
T2 - Biofilm formation and acid resistance
AU - Tokuda, Koichi
AU - Nishi, Junichiro
AU - Imuta, Naoko
AU - Fujiyama, Rika
AU - Kamenosono, Akira
AU - Manago, Kunihiro
AU - Kawano, Yoshifumi
N1 - Copyright:
Copyright 2010 Elsevier B.V., All rights reserved.
PY - 2010/6
Y1 - 2010/6
N2 - EAEC is increasingly recognized as an emerging enteric pathogen. Typical EAEC expressing the AggR regulon have been proven to be an important cause of childhood diarrhea in industrialized countries as well as in the developing world, while atypical EAEC without this regulon have not been thoroughly investigated. To investigate the bacteriological characteristics of EAEC, including both typical and a typical strains in Kagoshima, Japan, 2417 E. coli strains from Japanese children with diarrhea were screened by a quantitative biofilm assay to detect possible EAEC strains, resulting in the identification of 102 (4.2%) of these strains by the HEp-2 cell adherence test. Virulence gene patterns, PFGE analysis and O-sero grouping demonstrated the heterogeneity of the EAEC. The EAEC strains were classified into two groups: typical EAEC with aggR (74.5%, 76/102) and atypical EAEC without aggR (25.5%, 26/102). There was no significant difference between the typical EAEC strains (median OD570 = 0.73) and the atypical strains(medianOD570=0.61) in biofilm formation (P=0.17). Incidences of resistance against ampicillin, cefotaxime and tetracycline were significantly higher in the typical EAEC strains than the atypical EAEC strains (84.2% vs. 53.8%, 36.8% vs. 7.7% and 93.4% vs. 73.1%, respectively, P < 0.05). The typical EAEC strains showed significantly higher resistance ratios against HCl and lactate than the atypical strains (94.7% vs. 61.5% and 92.1% vs. 57.7%, respectively, P < 0.001). To investigate the pathogenicity of not only typical but also atypical EAEC, further bacteriological and epidemiologic studies including atypical EAEC are needed.
AB - EAEC is increasingly recognized as an emerging enteric pathogen. Typical EAEC expressing the AggR regulon have been proven to be an important cause of childhood diarrhea in industrialized countries as well as in the developing world, while atypical EAEC without this regulon have not been thoroughly investigated. To investigate the bacteriological characteristics of EAEC, including both typical and a typical strains in Kagoshima, Japan, 2417 E. coli strains from Japanese children with diarrhea were screened by a quantitative biofilm assay to detect possible EAEC strains, resulting in the identification of 102 (4.2%) of these strains by the HEp-2 cell adherence test. Virulence gene patterns, PFGE analysis and O-sero grouping demonstrated the heterogeneity of the EAEC. The EAEC strains were classified into two groups: typical EAEC with aggR (74.5%, 76/102) and atypical EAEC without aggR (25.5%, 26/102). There was no significant difference between the typical EAEC strains (median OD570 = 0.73) and the atypical strains(medianOD570=0.61) in biofilm formation (P=0.17). Incidences of resistance against ampicillin, cefotaxime and tetracycline were significantly higher in the typical EAEC strains than the atypical EAEC strains (84.2% vs. 53.8%, 36.8% vs. 7.7% and 93.4% vs. 73.1%, respectively, P < 0.05). The typical EAEC strains showed significantly higher resistance ratios against HCl and lactate than the atypical strains (94.7% vs. 61.5% and 92.1% vs. 57.7%, respectively, P < 0.001). To investigate the pathogenicity of not only typical but also atypical EAEC, further bacteriological and epidemiologic studies including atypical EAEC are needed.
KW - Acid resistance
KW - Biofilm
KW - Enteroaggregative escherichia coli
KW - Typical and atypical EAEC
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U2 - 10.1111/j.1348-0421.2010.00210.x
DO - 10.1111/j.1348-0421.2010.00210.x
M3 - Article
C2 - 20536730
AN - SCOPUS:77953590130
VL - 54
SP - 320
EP - 329
JO - Microbiology and Immunology
JF - Microbiology and Immunology
SN - 0385-5600
IS - 6
ER -