    New chain ID            Original chain ID

6uwi-pdb-bundle1.pdb:
           A                         A
           G                         G
           F                         F
           E                         E
           D                         D
           C                         C
           B                         B
           H                         H
           I                         I
           J                         J
           K                         K
           L                         L
           M                         M
           N                         N
           a                         a
           g                         g
           f                         f
           e                         e
           d                         d

6uwi-pdb-bundle2.pdb:
           c                         c
           b                         b
           h                         h
           i                         i
           j                         j
           k                         k
           l                         l
           m                         m
           n                         n
