    New chain ID            Original chain ID

8rrv-pdb-bundle1.pdb:
           B                         B
           E                         E

8rrv-pdb-bundle2.pdb:
           G                         G
           J                         J
           A                         A
           D                         D
           H                         H
           I                         I
           C                         C
           F                         F
           K                         K
           M                         M
