    New chain ID            Original chain ID

7z13-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
           H                         H
           I                         I
           J                         J
           K                         K
           L                         L
           M                         M
           N                         N
           O                         O
           P                         P
           Q                         Q
           a                         a
           b                         b
           c                         c
           d                         d

7z13-pdb-bundle2.pdb:
           e                         e
           f                         f
