Figure 9. Electron density omit map for Gly⁵⁸, Trp⁵⁹ and Glu⁶⁰ in the active site of the G89P variant of FKBP12 at 1.20 Å resolution.

Viewed along the plane of the indole ring for the major conformer (occupancy of 0.71), electron density for the perpendicular orientation of the minor conformer is apparent readily. The carbonyl oxygen in the minor conformer of Glu⁶⁰ (occupancy of 0.34) is shifted away from the canonical α-helical hydrogen-bonding geometry seen in the major conformer and to a position close to that observed in the wild-type FKBP12 structure [31]. The contour level for the electron density grid is 0.1261 e/ų=2σ.