A collection of residues from a PDB structure.

This class provides code to work with SCOP domain definitions. These are concisely expressed as one or more chain fragments. For example, “(1bba A:10-20,B:)” indicates residue 10 through 20 (inclusive) of chain A, and every residue of chain B in the pdb structure 1bba. The pdb id and brackets are optional. In addition “-“ indicates every residue of a pbd structure with one unnamed chain.

Start and end residue ids consist of the residue sequence number and an optional single letter insertion code. e.g. “12”, “-1”, “1a”, “1000”

pdbid — An optional PDB id, e.g. “1bba”

fragments — A sequence of tuples (chainID, startResID, endResID)