Figure 4

N-SH2 crystallographic and simulation-average secondary structures and Gly67 C_α – Asn92 C_α distances. Secondary-structure that is the same in all of the crystal and simulation structures is in plain text, secondary-structure corresponding to that in the isolated N-SH2 crystal is in bold, secondary-structure corresponding to that in the full SHP-2 crystal is in bold italics, and secondary structure corresponding to neither crystal structure is in bold underline. Vertical lines denote the spans of the EF (residues 66–68) and BG (residues 89–92) loops. The φ/ψ diagram was generated using the distribution of non-Gly, non-Pro backbone angles in a high-resolution x-ray crystal data set of 500 proteins [46]. The data were binned in 15° × 15° intervals, the natural logarithm of the histogram counts were taken, and contours have been drawn every 2 units. "E" = extended, "H" = helix, "L" = left-handed helix, "G" = gamma, and "2" = II'.