Adhesion of bacteria mediated by fimbriae is the initial stage of infection. Our purpose in the experiments herein described was to confirm the role of fimbrial adhesin(or fimbrial antigen complex:FAC) in binding to epithelial cell(HeLa) and to
characterize the fimbrial adhesin, The degree of fimbriation in E.coli was measured by electron microscope by means of negative staining with phosphotungstic acid. Purified fimbrial adhesin of E. coli was prepared by gel permeation
chromatography,
and
the molecular weight was measured by SDS-PAGE. The molecular weight of the adhesion was about 18,000 dalton. The effect of fimbriae on adherence to HeLa cell was investigated. The chromosomal and plasmid DNA fragments from E. coli were
transformed
into
competent E. coli DH5α. Transformants were detected by dot-blot immunoassay using rabbit anti-fimbrial adhesin serum. Plasmid preparation from transformants were analyzed. The results indicated that adherence of the tranformants with the 23 Kbp
or
2
Kbp recombinant plasmid were significantly increased in adherence to HeLa cells. Especially transformants which had the recombinant plasmids with insertion of both 23 and 2 Kbp DNA, were showed more increased adherence on HeLa cells when compared
with
E. coli DH5α as negative control. Therefore, it was suggested that these recombinant plasmids had great important roles in adherence to HeLa cells. But all of the transformants, from E. coli 297 and E. coli 298 with actin accumulation, had not
shown to
be actin accumulation which was detected by FAS test. Although these insert DNAs, especially 2Kb insert DNA, were suspected to be an eae gene concerned with actin accumulation, it could not be confirmed.
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