FIG 3.

Scanning electron microscopy of atomic force microscopy cantilevers confirms adhesion of E. coli to the cantilevers. Approximately 2 × 10⁷ E. coli CFU were added to the tip of the cantilever precoated with poly-l-lysine. After a 20-min incubation in PBS, cantilevers were incubated in DMEM/F-12 for another hour (or not, to determine potential of the bacteria to wash off). Cantilevers were fixed with 2.5% glutaraldehyde, sputter coated with gold, and visualized on an FEI XL30 SEM device. Equivalent numbers of E. coli organisms grown alone (A) and E. coli organisms grown in C. jejuni-CM (B) were observed. Furthermore, cell culture medium did not rinse the E. coli off the cantilever, since equivalent numbers of E. coli organisms grown alone (C) and E. coli organisms grown in C. jejuni-CM (D) were still observed after a 60-min incubation in DMEM/F-12.