    New chain ID            Original chain ID

9j1l-pdb-bundle1.pdb:
           1                         1
           2                         2
           3                         3
           A                         A
           B                         B
           C                         C
           I                         I
           N                         N
           O                         O
           P                         P
           Q                         Q
           R                         R
           n                         n
           o                         o
           p                         p
