    New chain ID            Original chain ID

6fec-pdb-bundle1.pdb:
           1                         1
           2                         2
           3                         3
           4                         4
           5                         5
           6                         6
           7                         7
           8                         8
           9                         9
           A                         A
           F                         F
           G                         G
           H                         H
           I                         I
           J                         J
           K                         K
           L                         L
           N                         N
           P                         P
           Q                         Q
           R                         R
           S                         S
           U                         U
           V                         V
           W                         W
           X                         X
           Y                         Y
           Z                         Z
           a                         a
           b                         b
           c                         c
           d                         d
           e                         e
           f                         f
           g                         g
           h                         h

6fec-pdb-bundle2.pdb:
           i                         i
           j                         j
           k                         k
           l                         l
           m                         m
           n                         n
           o                         o
           p                         p
           q                         q
           r                         r
           s                         s
           t                         t
           u                         u
           w                         w
