The accuracy of prediction was assessed by comparison to DSSP
[52]. We applied the same 8 to 3 state reduction scheme
throughout. E and B were taken as strand, H as helix and all other
states were taken as coil. This removes the 310-helix state from
the definition, but given that the 310-helix state represents a
weak 1 kcal/mol hydrogen bond, this seems reasonable, as it does not
normally represent core secondary structure. Single residue
-bridges (B) were included, as they do form part of core
structures, however these structures are typically difficult to
predict accurately. Removing single
residue
-bridges improves the apparent average Q3 prediction
accuracy by at least 1% (data not shown).