Lego_auto_mc [id two atoms] or [mol res1 res2]
Automatically build the main chain for a zone of atoms, using the database. This option goes along the chain searching for the best fitting pentapeptide, keeping the main chain atoms of the middle 3 residues and overlapping with the next pentapeptide. This means that the first and last residues are not changed. The option requires coordinates for the CA atom of each residue.