    New chain ID            Original chain ID

7pil-pdb-bundle1.pdb:
           A                        AA
           B                        AB
           C                        AC
           D                        AD
           E                        AE
           F                        AF
           G                        AG
           H                        AH
           I                        AI
           J                        AJ
           K                        AK
           L                        AL
           M                        AM
           N                        AN
           O                        BA
           P                        BB
           Q                        BC
           R                        BD
           S                        BE
           T                        BF
           U                        BG
           V                        BH
           W                        BI
           X                        BJ
           Y                        BK
           Z                        BL
           a                        BM
           b                        BN
           c                         H
           d                         L
           e                         M
           f                        UU
           g                         X
