    New chain ID            Original chain ID

9ygv-pdb-bundle1.pdb:
           A                         1
           B                         3
           C                         5
           D                         7
           E                         8
           F                         A
           G                         B
           H                         C
           I                         D
           J                         E
           K                         F
           L                         I
           M                         J
           N                         M
           O                         R
           P                         b
           Q                         6
           R                        10
           S                        11
           T                        13
           U                        15
           V                        16
           W                        17
           X                        19
           Y                         2
           Z                         4
           a                         9
           b                         L
           c                         a
