    New chain ID            Original chain ID

4v4n-pdb-bundle1.pdb:
           A                        A7
           B                        A8
           C                        Af
           D                        AQ
           E                        AS
           F                        AT
           G                        AU
           H                        AW
           I                        AX
           J                        B1
           K                        B2
           L                        B3
           M                        BA
           N                        BB
           O                        BC
           P                        BD
           Q                        BE
           R                        BF
           S                        BG
           T                        BH
           U                        BI
           V                        BJ
           W                        BK
           X                        BL
           Y                        BM
           Z                        BN
           a                        BO
           b                        BP
           c                        BQ
           d                        BR
           e                        BS
           f                        BT
           g                        BU
           h                        BV
           i                        BW
           j                        BX
           k                        BY

4v4n-pdb-bundle2.pdb:
           A                        A1
           B                        A3
           C                        A5
           D                        AA
           E                        Aa
           F                        AB
           G                        Ab
           H                        AC
           I                        AD
           J                        Ad
           K                        AE
           L                        Ae
           M                        AF
           N                        AG
           O                        Ag
           P                        AH
           Q                        Ah
           R                        AI
           S                        Ai
           T                        AJ
           U                        Aj
           V                        AK
           W                        Ak
           X                        AL
           Y                        AM
           Z                        AN
           a                        AO
           b                        AP
           c                        AR
           d                        AV
           e                        AY
           f                        AZ
