    New chain ID            Original chain ID

7l20-pdb-bundle1.pdb:
           A                         A
           B                         B
           D                         D
           F                         F
           H                         H
           K                         K
           L                         L
           M                         M
           O                         O
           R                         R
           S                         S
           T                         T
           W                         W
           X                         X
           Y                         Y
           Z                         Z
           0                         0
           1                         1
           2                         2
           3                         3
           4                         4
           8                         8
           b                         b
           e                         e
           g                         g
           i                         i
           j                         j
           m                         m
           o                         o
           q                         q
           r                         r
           J                         J
           I                         I
           N                         N
           P                         P
           U                         U
           V                         V
           E                         E
           5                         5
           6                         6
           7                         7
           9                         9
           a                         a
           c                         c
           d                         d
           f                         f
           h                         h
           k                         k
           l                         l
           p                         p

7l20-pdb-bundle2.pdb:
           A                         s
           B                         Q
           C                         u
           D                        TA
           E                        TB
           F                        TC
           G                         z
           H                         w
