Figure 3 - full size

Figure 3.
Fig. 3. Structure of the F71N, F82Q, and F92N p18^INK4c mutants in comparison to the native structure of p18^INK4c protein. a, superposition of the mutant, F71N (in green) and the native protein (in gray) along with the simulated annealing omit map around the site of mutation contoured at 1.5 . The yellow sphere represents a water molecule. b, detailed interactions made in the F71N p18^INK4c mutant are shown in green with CPK coloring, while the structure of the native protein, which lacks these new interactions are shown in gray. The mutation results in a new hydrogen-bonding interaction with arginine 79, and a water (shown in yellow)-mediated hydrogen bond with aspartate 100. Glycines are shown as green or gray spheres. c, same as a except that the F82Q mutant is shown. d, detailed interactions made in the F82Q p18^INK4c mutant are shown in green with CPK coloring, while the structure of the native protein, which lacks these, new interactions are shown in gray. The mutation results in new hydrogen bonding interaction with the backbone NH of glycine 48 and a water (shown in yellow)-mediated hydrogen bond with arginine 117. Glycines are shown as green or gray spheres. e, same as a except that the F92N mutant is shown. f, detailed interactions made in the F92N p18^INK4c mutant are shown in green with CPK coloring, while the structure of the native protein, which lacks these, new interactions are shown in gray. The mutation results in a new water-mediated hydrogen bond with arginine 54. Glycines are shown as green or gray spheres. Molscript objects for the electron density was created using CONSCRIPT, and the figures were prepared with the programs MOLSCRIPT (37) and RASTER3D (38).