Figure 2. Applicability of bulky halogenation on tyrosine residues for protein stabilization.

(a) Distribution of the sizes of the spaces near the 51,504 tyrosine meta positions in 2,168 proteins. There are 13,000 instances outside the indicated size range. The size range for the spaces potentially able to accommodate the bromine or chlorine atom is indicated by the grey bar. (b) Unfolding curves against a chemical denaturant for the wild-type azoreductase (, dotted line) and the three-site brominated variant (, solid line). The fraction of unfolded molecules is plotted against the urea concentration.