Scheme 1.

Primary sequence and 3D structure of Tβ4 (PDB: 4PL7). Amino acids in parentheses were not defined by the X-ray structure and were added using Modeller v. 10.0 following the proper secondary structure elements (alpha helix). The metal-binding sites (I–IV) are signed in red. The scheme was created by Joanna Izabela Lachowicz, University of Cagliari. This image is original and designed specifically for the targeted publication. It should not be cropped, distorted, or in any way edited without the expressed consent of Research Publication Services.