Fig. 2.

Alignment of the N-terminus (first 54 amino acids) of mature type IVa PilA proteins from various taxonomic groups. The numbers in parentheses represent the size of the mature pilin protein and the percentage similarity to PilA from Geobacter sulfurreducens. The Lesk color scheme was used to shade the amino acids. All small nonpolar residues (G, A, S, T) are orange; all hydrophobic residues (C, V, I, L, P, F, Y, M, W) are green; all polar residues (N, Q, H) are magenta; all negatively charged (D, E) are red; and all positively charged residues (K, R) are blue.