Table 2: The conserved amino acids or groups of amino acids according to the standard numbering scheme for the N- or C-terminal expansin domain, with the sequence of Bacillus subtilis (PDB accession 4fer) as reference sequence. All positions are listed separately for superfamilies 1 ”Bacterial expansins”, 2 ”Fungal expansins”, and 3 ”Plant expansins” that are at least conserved to 70%. Positions marked in the standard numbering scheme as inaccurate are excluded (described in the Methods section). The last column names the function and the motif known from literature9,55. If a single amino acid is at least conserved to 70%, the conservation of the respective amino acid group is not mentioned. Amino acid groups: non-polar (A, C, F, G, I, L, M, P, V, W)40; polar (D, E, H, K, N, Q, R, S, T, Y)40.