Pilins of fimbrial adhesins of different member species of Enterobacteriaceae are structurally similar to the C-terminal half of adhesin proteins.

The structural relatedness of pilins and the C-terminal half of adhesin proteins in different member species of Enterobacteriaceae was deduced from their two-dimensional sequence analysis using the hydrophobic cluster analysis (HCA) and secondary structure predictions from the profile network Hei-Delberg program (PHD). Despite a large evolutionary distance between the two protein families, we show that pilins and the C-terminal domain of adhesins have a similar folding that can serve as modules for pilus assembly.