Residue Count (max +100)
Penalizes a residue count above 80 by 20 Foldit points per additional residue. The count is capped at 85.
Why are the prolines on the frozen backbone mutable?
A poly-proline helix doesn't have to be made entirely of proline. Any set of residues that adopt the appropriate dihedral angles can be classified as a poly-proline helix. Proline is simply one of the few amino acids that can easily do so.