The transition state for orotidine monophosphate decarboxylation. The
mechanism of OMP decarboxylase, the most proficient of all enzymes is
predicted by Jeehiun K. Lee and K. N. Houk to involve protonation of
N-4 in a nonpolar cavity (Science, 1997, 276, 942-925).
This art illustrates some of the research of Prof. Ken Houk's group at UCLA.
Note: the images here are reduced in color depth and resolution for viewing
on the web. They are not print quality.