Figure 2.
Figure 2. Inducer binding site. (a) The fit of IPTG to the
difference electron density where the phases were calculated
from the atomic model of the repressor. The inducer and the
water molecules were omitted from the structure factor
calculations. The difference electron density was contoured at
3.5σ. (b) The binding of the inducer to the repressor. The view
is rotated vert,
similar 90° from (a) to better illustrate the detailed
hydrogen bonding network. The dark blue portions of the
structure correspond to residues in the C-terminal domain while
the light blue corresponds to the N-terminal portion of the
structure. The inducer and the water-mediate hydrogen bonds
stabilize this conformation of the repressor. The green broken
lines illustrate the water-mediated hydrogen bonding network
that links the N-terminal and C-terminal sub-domains.
vert,
similar 90° from (a) to better illustrate the detailed
hydrogen bonding network. The dark blue portions of the
structure correspond to residues in the C-terminal domain while
the light blue corresponds to the N-terminal portion of the
structure. The inducer and the water-mediate hydrogen bonds
stabilize this conformation of the repressor. The green broken
lines illustrate the water-mediated hydrogen bonding network
that links the N-terminal and C-terminal sub-domains.