FIG 4 .

Vegetative cell and spore adherence to Caco-2 cells. Caco-2 cell monolayers were incubated for 2 h with washed vegetative cells or spores of CN3718, CN3718::codY, and CN3718comp at 37°C under anaerobic conditions. Monolayers were then washed three times with HBSS buffer and lysed in HBSS buffer, and total bacteria or spores were plated onto BHI agar plates for counting. For spore counting, the collected spores were heat shocked for 20 min at 70°C before plating. Attachment was then expressed as the percentage of attached bacteria or spores relative to the total number of input bacteria or spores. *, P < 0.05 (Student’s t test, compared to wild type). All experiments were repeated three times, and mean values are shown. The error bars indicate standard deviations.