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| Author(s): |
Claudia de Oliveira Ayala
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI) |
| Defense date: | 2009-11-19 |
| Examining board members: |
Antonio Fernando Pestana de Castro;
Vania Maria de Carvalho;
Marcia Regina Franzolin;
Roxane Maria Fontes Piazza;
Tania Mara Ibelli Vaz
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| Advisor: | Antonio Fernando Pestana de Castro |
| Abstract | |
The Escherichia coli species consists of a group of typically non-pathogenic bacteria present in the intestinal tract of humans and animals. Strains are serotyped according to their O (somatic), H (flagellar) and K (capsular) surface antigens, in order to distinguish these microorganisms from the non-pathogenic members of the intestinal microbiota. The flagellar antigen corresponding to the filament is formed by the polymerization of the flagellin, codified by the fliC gene. This study employed the PCR-RFLP technique to analyze flagellar antigen patterns from 112 EPEC and STEC strains. Fourteen strains have not amplified the fliC gene, 17 had their flagellar antigen determined only by the PCR-RFLP and 75 strains had their flagellar antigen confirmed by this technique. Three H antigens with irregular patterns were cloned and sequenced. After sequencing, insertions and deletions of nucleotides were discovered. So far, few studies used a significant number of STEC and EPEC strains originated from different animals to determine H antigens employing the PCR-RFLP technique of the fliC gene. According to the findings of this study, we assumed that PCR-RFLP of the fliC gene is faster, less laborious and more efficient than classic serotyping methodology. (AU) | |