    New chain ID            Original chain ID

9r2s-pdb-bundle1.pdb:
           A                        Pb
           B                        Pe
           C                        Pa
           D                        Pc
           E                        Pd
           F                        Pg
           G                        Po
           H                        Pf
           I                        Pq
           J                        Pi
           K                        Pn
           L                        Pm
           M                        Ph
           N                        Pl
