    New chain ID            Original chain ID

7yfe-pdb-bundle1.pdb:
           1                         1
           2                         2
           3                         3
           4                         4
           5                         5
           A                         A
           B                         B
           C                         C
           D                         D
           E                         E
           H                         H
           I                         I
           J                         J
           K                         K
           L                         L
           M                         M
           N                         N

7yfe-pdb-bundle2.pdb:
           R                         R
           T                         T
           U                         U
           a                         a
           b                         b
           c                         c
           d                         d
           e                         e
