    New chain ID            Original chain ID

9n7a-pdb-bundle1.pdb:
           A                        L1
           B                        L2
           C                        L3
           D                        L4
           E                        L5
           F                        L6
           G                        L7
           H                        L8
           I                        L9
           J                        LC
           K                        LD
           L                        LE
           M                        LF
           N                        LG
           O                        N2
           P                        NA
           Q                        NB
           R                        NF
           S                        NG
           T                        NL
           U                        NM
           V                        NP
           W                        NQ
           X                        NS
           Y                        NW
           Z                        SG
           a                        SH
           b                        SI
           c                        SJ
           d                        SK
           e                        SL
           f                        SM
           g                        SP
           h                        SR
           i                        SS
           j                        ST
           k                        SU
           l                        SW
           m                        SZ
