    New chain ID            Original chain ID

6n2d-pdb-bundle1.pdb:
           A                        b2
           B                        b1
           C                         a
           D                        c0
           E                        c1
           F                        c2
           G                        c3
           H                        c4
           I                        c5
           J                        c6
           K                        c7
           L                        c8
           M                        c9
