    New chain ID            Original chain ID

7rnl-pdb-bundle1.pdb:
           B                         B
           A                         A
           C                         C
           D                         D
           H                         H
           E                         E
           K                         K
           N                         N
           I                         I
           F                         F
           L                         L

7rnl-pdb-bundle2.pdb:
           O                         O
           J                         J
           G                         G
           M                         M
           P                         P
