Escherichia coli S fimbriae do not contribute to intestinal colonization or translocation in the gnotobiotic rat

• Published in: Microbial pathogenesis Vol. 31; no. 2; pp. 103 - 107
• Main Authors: Herı́as, Veronica M., Robertson, Anna-Karin, Midtvedt, Tore, Wold, Agnes E.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-08-2001; Elsevier
• Subjects: Adhesins, Escherichia coli - genetics; Animals; Animals, Newborn; Animals, Suckling; Bacterial Adhesion; Bacteriology; Biological and medical sciences; Cells, Cultured; Epidemiology; Epithelium - microbiology; Escherichia coli; Escherichia coli - physiology; Escherichia coli, S fimbriae, colonization, translocation; Fimbriae Proteins; Fimbriae, Bacterial - physiology; Fundamental and applied biological sciences. Psychology; Germ-Free Life; Intestinal Mucosa - microbiology; Intestines - microbiology; Lymph Nodes - microbiology; Medicin och hälsovetenskap; Mesentery - microbiology; Microbiology; Mutagenesis, Insertional; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Rats; Escherichia coli, S fimbriae, colonization, translocation; Human; Neonatal; Sialic acid; Rat; Digestive system; Escherichia coli; Virulence; Rodentia; Population translocation; Infant; Pilus; Mucus; Small intestine; Feeding; Infection; Vertebrata; Mammalia; Bacteria; Epithelial cell; Isogenic line; Colonization; Enterobacteriaceae
• ISSN: 0882-4010; 1096-1208
• DOI: 10.1006/mpat.2001.0449

Escherichia coli S fimbriae, which bind to sialic acid residues, are a virulence factor for extraintestinal infection, but also promote binding to intestinal epithelial cells. In this study, we investigated whether S fimbriae would enhance intestinal colonization by E. coli or promote translocation to extraintestinal sites. A mixture of two E. coli isogenic strains both expressing type-1 fimbriae but differing in the carriage of S fimbriae (Sfim+ and Sfim−) were given perorally to germfree neonatal, infant or adult rats. The Sfim+ bound better to rat intestinal mucus and epitheial cells. However, both strains colonized equally well in both the small and large intestine and their rate of translocation to the mesenteric lymph nodes was similar. Infant rats had higher E. coli levels in the small intestine than adult rats, but their translocation rates were lower. This was at least partly due to their milk diet, since weaned infant rats had more translocating bacteria than infant rats that continued suckling their mother. The results suggest that S fimbriae, despite binding to intestinal epithelial cells and mucus, do not contribute to either colonization or translocation in the gnotobiotic rat.