Fig. 3.

Tetra-tandemer structures. Crystal structures of the (A) MhLap, PDB code: 6XI3 (this study), (B) AhLap, PDB code: 6XI1 (this study), and (C) MpIBP, PDB code: 4P99 (Vance et al., 2014) tetra-tandemers, as well as the SiiE tri-tandemer, PDB code: 2YN3 (Griessl et al., 2013). Calcium ions are shown as gold spheres. The repeats rotate down a central axis of varying periodicity and direction. Views down that axis from N to C terminus are shown for MhLap (D), AhLap (E), and MpIBP (F), along with their direction and the relative position of repeats.