| Project/Area Number |
01480547
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
基礎獣医学
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| Research Institution | National Institute of Health (1991)
Hokkaido University (1989-1990) |
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Principal Investigator |
NAIKI Masaharu NIH Dept. of Vet. Sci. Director, 獣疫部, 部長 (10020752)
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| Project Period (FY) |
1989 – 1991
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| Project Status |
Completed (Fiscal Year 1991)
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| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1991: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1990: ¥1,000,000 (Direct Cost: ¥1,000,000)
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| Keywords | E. coli / diarrhea / fimbriae / fimbrial vaccine / adhesoin / ganglioside / GM3 / N-glycolylneuraminic acid / プラスミド / 病原性大腸菌 / 線毛遺伝子 / 糖脂質 / ブタ / ウシ |
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| Research Abstract |
Enterotoxigenic E. coil with K99 fimbrial antigen causes diarrhea in newborn calves, piglets and lambs. The fimbriae consist of 8 subunits ; a major subunit called fimbrillin forms fimbrial structure and a minor subunit celled adhesion locates at the tip of fimbriae. Adhesoin recognizes carbohydrate epitope on the surface of host intestinal mucosa. In this project, adhesoin gene was identified, and host receptor glycosphingolipid structure and postnatal change in content were determined.
1)Among 8 fimbrial genes(fana to fanh), DNA sequences of fanE and fanF which were still unknown were analyzed. The sequence of fanf had E. coli, therefore, fanf product seems to be adhesoin. However, fanF product did not show adhesoin activity. Both fanf and fane products were necessary for showing the activity.
homology to those of other adhesoin genes from different kinds of
2)Ganglioside GM3(NeuGc) : NeuGcalpha2-3Galbeta1-4Glc-Cer was a major glycosphingolipid component in intestinal mucosa from newborn calves and piglets. This ganglioside was bound by ^<125>I-labelled bacteria. The most potent affinity for the binding was detected in a major component of the ganglioside with 2-hydoxyl C16 fatty acid and phytosphingosine. The high affinity component dramatically decleased in the content after birth ; 50% at 1-week age, 30% at 2-week age and only 2y. at adult age. The decrease of the receptor molecule can explain the age registance of the E. coli infection.
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