    New chain ID            Original chain ID

9u4r-pdb-bundle1.pdb:
           A                        AA
           B                        AB
           C                        AC
           D                        AD
           E                        AE
           F                        BA
           G                        BB
           H                        BC
           I                        BD
           J                        BE
           K                        BG
           L                        BH
           M                        BI
           N                        BJ
           O                        BK
           P                        BL
           Q                        BM
           R                        BN
           S                        CA
           T                        CB
           U                        CC
           V                        CD
           W                        CE
           X                        CF
           Y                        CG
           Z                        CH
           a                        CI
           b                        CJ
           c                        CK
           d                        DA
           e                        DB
           f                        DC

9u4r-pdb-bundle2.pdb:
           A                        DD
           B                        DE
           C                        DF
           D                        DG
           E                        DH
           F                        DI
           G                        DJ
           H                        DK
           I                        EA
           J                        EB
           K                        EC
           L                        ED
           M                        EE
           N                        EF
           O                        EG
           P                        EH
           Q                        EI
           R                        EJ
           S                        EK
           T                        FA
           U                        FB
           V                        FC
           W                        FD
           X                        FE
           Y                        FF
           Z                        FG
           a                        FH
           b                        FI
           c                        FJ
           d                        FK
           e                        GA
           f                        GB
           g                        GC

9u4r-pdb-bundle3.pdb:
           A                        GD
           B                        GE
           C                        GF
           D                        GG
           E                        GH
           F                        GI
           G                        GJ
           H                        GK
