    New chain ID            Original chain ID

7pfo-pdb-bundle1.pdb:
           2                         2
           3                         3
           4                         4
           5                         5
           6                         6
           7                         7
           A                         A
           B                         B
           C                         C
           D                         D
           E                         E
           F                         F

7pfo-pdb-bundle2.pdb:
           G                         G
           H                         H
           I                         I
           J                         J
           K                         K
           L                         L
           M                         M
           N                         N
           Q                         Q
