Fig 1.

Characterization of an S. Typhimurium mutant carrying an unmarked deletion of csgBA genes. Expression of curli fibrils was detected by flow cytometry (A) and Western blotting (B). Cellulose production was monitored on plates containing calcofluor (C). Motility was determined on plates containing 0.3% agar (D). Invasiveness of strains was tested using human colonic epithelial (HT-29) cells (E). Each experiment was repeated three times independently, with similar outcomes, and a representative example is shown.