PREDITOR will always generate a torsion angle prediction. However, in some cases the error limits or uncertainty are too large to be of practical use. This situation can arise when the protein is particularly rich in beta-sheet content (>50%), when it is mostly denatured or when no strong (>50% ID) homologues exist in the PDB. In these cases it is probably wise to obtain torsion angle restraints via other experimental methods (J-couplings, cross-relaxation or NOE approaches). Deciding whether to use or discard PREDITOR predictions is largely up to the user and their own particular circumstances. Unfortunately there is no hard and fast rule that we can offer at this time. While the performance of PREDITOR for helical and mixed alpha/beta proteins is quite acceptable, the performance for beta-rich proteins still indicates some room for improvement. |