Fig. 6
Comparison of binding modes for the FK506-binding protein (FKBP) domain. a Superimposition of the FKBP domains of TtSlyDFL:S2-W23A molecule B (purple), TtSlyDFL:S2-W23A molecules D (light blue), and TtSlyDFL:FK506 (yellow), showing the variation in interactions with the backbone of N35–I37. Selected amino acid residues and FK506 atoms are labeled. b Same overlay but showing instead the interaction with Y63. c Superimposition of the FKBP domains of all full-length TtSlyD (TtSlyDFL) molecules in the TtSlyDFL:S2-W23A, TtSlyDFL:S2, TtSlyDFL:FK506, and TtSlyDFL:S2-plus2 structures, showing how the orientation of the insert-in-flap (IF) domain varies with the position of Y63, and thus with which substrate is bound. TtSlyDFL molecules binding the peptides in the type VIa1 or VIb-like modes are purple and light blue, respectively, TtSlyDFL:FK505 is yellow, and TtSlyDFL:S2-plus2 (apo form) is gray