8.8 years ago by
"I want to predict folds for the remaining 20% of the structures also."
IMHO, you cannot assign an existing SCOP class to these entries, because these 20% are novel .
It is true that approximately 20% of proteins in PDB is not associated with any known SCOP classification. SCOP curators are well aware of these group of structures. This 20% structures are not assigned a classification due to the sequence-structure diversity of those structures with rest of the members in PDB. For example the structures my contain additional embellishments in structure that will disqualify them from being a member of a particular fold/class. Some of these may get merged into existing classes in the future or depending upon the number of new members with similar features, it may add to a novel fold. As large part of SCOP is manually curate, you may need to wait until SCOP curators assign a fold details to these entries.