Figure 4.
Fig. 4. Purine repressor DNA binding site in free and
protein-bound crystal structures. (a) The PurR dodecamer
(5′-GCAAACGTTTGC-3′)[2] adopts a straight B-DNA structure.
(b) The protein-bound binding site^23 is bent vert,
similar 50° towards the major groove at the central CG base
pair (top right, PDB ID 1qpz). The DNA binding region of the
purine repressor is shown as a semi-transparent surface. The
color scheme is as described for Fig. 1.
vert,
similar 50° towards the major groove at the central CG base
pair (top right, PDB ID 1qpz). The DNA binding region of the
purine repressor is shown as a semi-transparent surface. The
color scheme is as described for Fig. 1.