    New chain ID            Original chain ID

6y6x-pdb-bundle1.pdb:
           A                        L5
           B                        L7
           C                        L8
           D                        LA
           E                        LB
           F                        LC
           G                        LD
           H                        LE

6y6x-pdb-bundle2.pdb:
           A                        LF
           B                        LG
           C                        LH
           D                        LI
           E                        LJ
           F                        LL
           G                        LM
           H                        LN
           I                        LO
           J                        LP
           K                        LQ
           L                        LR
           M                        LS
           N                        LT
           O                        LU
           P                        LV
           Q                        LW
           R                        LX
           S                        LY
           T                        LZ
           U                        La
           V                        Lb
           W                        Lc
           X                        Ld
           Y                        Le
           Z                        Lf
           a                        Lg
           b                        Lh
           c                        Li
           d                        Lj
           e                        Lk
           f                        Ll
           g                        Lm
           h                        Ln
           i                        Lo
           j                        Lp
           k                        Lr
           l                        Lz
