Sequence and structural modules present in D assemblies. (A) VWD modules. (B) C8 modules. (C) Structure of a TIL domain (PDB code 1CCV) in a rainbow representation (blue N to red C) with cysteines numbered and disulfide bonds shown in yellow. (D) TIL modules. (E) E modules. (F) The unique D4N module. Cysteines characteristic of each type of module are numbered above the sequences and are color coded and connected with colored lines as follows: in panel A, all disulfides are defined chemically in 1 or both of D3 and D4; panels B and D through F, disulfide bonds defined chemically in D′D3 or D4 are shown as horizontal connecting lines above the alignments, except in 4 cases of disagreement with homology-defined disulfides (see supplemental Methods); and disulfides suggested by homology are shown as horizontal connecting lines below the alignments. Cleavage sites referred to in the text are marked with arrows. N- and O-linked glycosylation sites12 are shown in red.
