Fig 5.

Homology model of Hsp72 C306D NBD. (a) Pseudo-oxidation of residue 306 does not produce global changes in the NBD fold, similar to what was seen with the C267D mutant (see Fig 4). Green is C306D. Yellow is wild type (PDB 3JXU). The C306D and C267D models are nearly identical (see Fig. 4), with C306D also causing an ~25 Å total displacement of residues associated with nucleotide binding. (b) Close up that illustrates how C306D increases the solvent exposure of Cys267, potentially enhancing its oxidation. C267 moves by ~3 Å in the C306D model. (c) Model for initial oxidation at Cys306, leading to synergistic oxidation of C267 and reduced ATP binding.