Figure 2
The structure of the apo MATα1 R264H mutant. (a) The subunits of the MATα1 R264H dimer are shown as grey and blue ribbons. The dimer is composed of two self-assemblies of the R264H subunit (chains A and B). The Arg264His mutation site is shown in the Fo − Fc OMIT map contoured at the 3σ level (grey). The gating loop (113–131) and residues 250–259 are shown in green and pink, respectively. (b) His264 and Glu57 of each partner subunit form hydrogen bonds of 2.7 and 2.9 Å, aiding stabilization of the dimer. Hydrogen bonds are shown as black dotted lines. (c) The dimer interface of the MATα1 R264H mutant is shown. The substitution of Arg264 by His264 changes the distance between this residue of each subunit to 7.53 Å (Cα–Cα measurement), which is about 2.06 Å longer than the corresponding distance in the wild type. The Thr262–Ile266 main chains are shown as grey and blue sticks. |