FIG. 2.

Adherence of SpaCBA and SpaFED pilin proteins to human intestinal mucus. The methods used to determine binding between 50-pmol portions of radiolabeled (¹²⁵I) SpaCBA and SpaFED pilins and immobilized mucus and the methods used for the corresponding statistical analysis are described in Materials and Methods. The background level of mucus binding was based on the adherence of 50 pmol radiolabeled (¹²⁵I) ovalbumin to mucus. The binding data for three or four measurements are expressed as means ± standard deviations, and the differences between data sets are considered significant (P ≤ 0.05).