    New chain ID            Original chain ID

7asd-pdb-bundle1.pdb:
           A                        AA
           B                        AB
           C                        BA
           D                        BB
           E                        CA
           F                        CB
           G                        DA
           H                        DB
           I                        EA
           J                        EB
           K                        FA
           L                        FB
           M                        GA
           N                        GB
           O                        HA
           P                        HB
           Q                       AAc
           R                         A
           S                       BAc
           T                         B
           U                       CAc
           V                         C
           W                       DAc
           X                         D
           Y                       EAc
           Z                         E
           a                       FAc
           b                         F
           c                       GAc
           d                         G
           e                       HAc
           f                         H
