    New chain ID            Original chain ID

10mt-pdb-bundle1.pdb:
           A                         A
           B                         B
           C                         F
           D                         G
           E                         H
           F                         I
           G                         J
           H                         K
           I                         L
           J                         M
           K                         N
           L                         C
           M                        CA
           N                         D
           O                         E
           P                         a
           Q                         b
