    New chain ID            Original chain ID

9xhk-pdb-bundle1.pdb:
           A                         1
           B                         2
           C                         4
           D                        AA

9xhk-pdb-bundle2.pdb:
           A                        AB
           B                        AC
           C                        AD
           D                        AE
           E                        AF
           F                        AG
           G                        AI
           H                        AL
           I                        AM
           J                        AN
           K                        AO
           L                        AP
           M                        AQ
           N                        AR
           O                        AS
           P                        AT
           Q                        AU
           R                        AV
           S                        AW
           T                        AX
           U                        AY
           V                        AZ
           W                        Aa
           X                        Ab
           Y                        Ad
           Z                        Af
           a                        Ag
           b                        Ah
           c                        Ai
           d                        BA
           e                        BB
           f                        BC
           g                        BD
           h                        BE
           i                        BF
           j                        BG
           k                        BH
           l                        BI
           m                        BJ
           n                        BK
           o                        BL
           p                        BM
           q                        BN
           r                        BO
           s                        BP
           t                        BQ
           u                        BR
           v                        BS
           w                        BT
           x                        BU
           y                        BV
           z                        BY
           0                        BZ
           1                        Ba
           2                        Bc
           3                        CS
           4                        LF
