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Figure 5.
Figure 5 Stereo view of the superimposition of UMP-bound UPRTase
(red) and 5-fluorouracil-bound UPRTase (green) onto the
uracil-bound UPRTase (blue). Note the rotation of the
5-fluorouracil ring that occurs to prevent steric clash between
the fluorine atom and the C[ ]atom
of Ala168. Also, the slightly 'pulled out' position of the
uracil ring of the UMP moiety, compared with uracil, is
revealed. Labeled are residues Ala168, Tyr228, which stacks over
the uracil ring, and Asp235 which hydrogen bonds with the
Tyr228. Wat1 of each complex is shown as an appropriately
colored sphere. The double-headed arrow highlights the proximity
of the fluorine atom of 5-fluorouracil to the C[ ]atom
of Ala168. This figure was generated using O (Jones et al.,
1991).
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