Figure 7.

Example of alternate conformations correlated with partial water occupancy. The Glu side chain split at C^β assumes two approximately 60/40% occupied alternate conformations. The two water atoms are too close to be present at the same time, and their occupancies should be related to those of the associated side chains. The sum of the occupancies of the two groups must be constrained to 1.0. 2mF _o − DF _c electron density is contoured at the 1σ level. This figure was modified from Rupp (2009 ▶).