Figure 4.
(a) Stereo view of the binding pocket in the S[MK] box
riboswitch in complex with Se-SAM. The location of the selenium
atom is confirmed by the strong anomalous-difference density
shown in blue contoured at 8 .
The rest of the binding pocket in the Se-SAM–bound S[MK]
structure is almost identical to that in the SAM-bound
structure. Magenta mesh signifies the simulated composite omit
electron-density map of Se-SAM contoured at 1.5 .
(b) Stereo view of the SAH-bound S[MK] structure from a
direction similar to that shown in a. The simulated annealing
omit map contoured at 0.8 level
clearly shows that the ribose and sulfide moieties rotate
180° to exit the RNA from the linker helix side.
The above figure is reprinted
by permission from Macmillan Publishers Ltd:
Nat Struct Biol
(2008,
15,
1076-1083)
copyright 2008.
.
The rest of the binding pocket in the Se-SAM–bound S[MK]
structure is almost identical to that in the SAM-bound
structure. Magenta mesh signifies the simulated composite omit
electron-density map of Se-SAM contoured at 1.5