Specify template without alignment: If you want I-TASSER to use a specific PDB structure as a template, you can use this option specify the PDB structure. You only need to type in the PDBID:ChainID, e.g. 1wor:A without specifying the target-template alignments. I-TASSER will first fetch the structure from the PDB library and then generate the target-template alignment based on our in-house alignment tool, MUSTER.