    New chain ID            Original chain ID

7pd6-pdb-bundle1.pdb:
           A                       AaA
           B                       BaB
           C                       CaC
           D                       DaD
           E                       EaE
           F                       FaF
           G                       GaG
           H                       HaH
           I                       IaI
           J                       JJJ
