    New chain ID            Original chain ID

6x5i-pdb-bundle1.pdb:
           A                         B
           B                         D
           C                         E
           D                         F
           E                         G
           F                         H
           G                         I
           H                         J
           I                         K
           J                         L
           K                         M
           L                         N
           M                         O
           N                         P
           O                         Q
           P                         R
           Q                         S
           R                         T
           S                         U
           T                         V
           U                         W
           V                         X
           W                         Y
           X                         Z
           Y                         a
           Z                         b
           a                         c
           b                         d
           c                         e
           d                         f
           e                         g
           f                         h
           g                         i
           h                         j
           i                         k
           j                         l
           k                         m
           l                         n
           m                         o
           n                         p
           o                         q
           p                         r
           q                         s
           r                         t
           s                         u
           t                         v
           u                         w
           v                         x
           w                         y
           x                         z
           y                         0
           z                        AA
           0                        BA
           1                        CA
           2                        DA
           3                        EA
           4                        FA
           5                        GA
           6                        HA
           7                        IA
           8                        JA
           9                        KA

6x5i-pdb-bundle2.pdb:
           A                        LA
           B                        MA
           C                        NA
           D                        OA
           E                        PA
           F                        QA
           G                        RA
           H                        SA
