Calculated RSC for each pair of residues in DHFR. Red corresponds to a
large positive energetic connectivity, blue to the smallest
connectivity, and purple to a negative energetic connectivity, as
indicated in the color bar. Residues 1–34 (labeled A), residues 60–90
(labeled B), and residues 110–159 (labeled C) each behave
cooperatively. Additionally, residues 1–34 and 110–159, although
distal in sequence, are also positively cooperative (labeled D).