Prodar
Prodar searches the PDB for candidate protein structural alignments
...Searches are extremely fast, searching the PDB (included in app) in less than a minute typically.
Prodar identifies partial matches, such that a relatively small section of the query structure may be matched against sections of other structures in the PDB regardless of the relative size of the chains. The intention is that the tool automatically identifies common domains and motifs in otherwise dissimilar protein structures. These can then be structurally aligned in a different tool to find an RMSD (Prodar just makes suggestions).
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