    New chain ID            Original chain ID

7agx-pdb-bundle1.pdb:
           A                        1A
           B                        1B
           C                        1C
           D                        1D
           E                        1E
           F                        1F
           G                        1G
           H                        1H
           I                        1I
           J                        1J
           K                        1K
           L                        1L
           M                        1M
           N                        1N
           O                        1O
           P                        1P
           Q                        2A
           R                        2B
           S                        2C
           T                        2D
           U                        2E
           V                        2F
           W                        2G
           X                        2H
           Y                        2I
           Z                        2J
           a                        2K
           b                        2L
           c                        2M
           d                        2N
           e                        2O
           f                        2P
           g                        2Q
