Figure 1
Overview of the structure and oligomerization behavior of RcoTetpLS20. (a) The sequence and secondary-structure prediction using JPred4 (Drozdetskiy et al., 2015) of full-length RcopLS20. The rectangles indicate the HTH domain at the N-terminus as annotated in UniProt entry E9RIY8 and the RcoTetpLS20 domain corresponding to the crystallized fragment. The amino-acid letters are colored according to secondary structure in the crystal structure (green for β-strand and red for α-helix). (b) Cartoon representation of residues Val125–Tyr155 of the RcoTetpLS20 dimer, colored by chain. All side chains are shown as sticks; the numbers of selected residues of the green monomer are indicated. A monomer of the p53 structure (PDB entry 1aie; Mittl et al., 1998), superposed on the green monomer of RcopLS20, is shown in transparent gray. (c) Side view of the tetrameric structure, showing the two charged layers formed by the Arg141 and Glu145 residues from the four monomers and the way each of these clusters is capped by a pair of Leu148 residues. (d) Close-up view of a single Arg141/Glu145 layer and Leu148 cap. The hydrogen bonds between the residues of the charged cluster are indicated by yellow dotted lines. (e) Electrostatic potential (ESP) on the surface of the tetrameric structure of RcoTetpLS20 in two orientations. The orientation shown in the left panel is similar to that shown in Fig. 1(b). In the right panel, RcoTetpLS20 is rotated by 90° around a vertical axis, showing the ESP of the view on the exposed face of the β-strands. (f) Superposed SEC elution profiles of RcoTetpLS20 at different pH values. |