E. Double immunofluorescent staining of Fn12230, fadA-deletion mutant US1 (∆fadA) and spontaneous mutant lam in log and stationary phases using mAb 7H7 at 1:800 dilution and anti-human β-amyloid polyclonal antibody A11 at 1:500 dilution, followed by incubation with Alexa Fluor 680-conjugated donkey anti-rabbit and Alexa Fluor 555-conjugated goat anti-mouse, both at 1:1,000 dilution. Co-staining of FadA and A11 was observed in Fn in stationary phase, not in log phase, or in US1 or lam. The imagines were taken under 60X objective. Scale bar equals 5 μm. 