Sequence alignment between 6f1f(A) and UniProt seq P00974 (BPT1_BOVIN):

P00974 (BPT1_BOVIN): Pancreatic trypsin inhibitor from Bos taurus
                 10        20        30        40        50        60        70        80        90       100
         ---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
UniProt: MKMSRLCLSVALLVLLGTLAASTPGCDTSNQAKAQRPDFCLEPPYTGPCKARIIRYFYNAKAGLCQTFVYGGCRAKRNNFKSAEDCMRTCGGAIGPWENL
         ................................................X...................................................
PDB seq: -----------------------------------RPDFCLEPPYTGPXKARIIRYFYNAKAGLCQTFVYGGCRAKRNNFKSAEDCMRTCGG--------
                                            ---------+---------+---------+---------+---------+-------        
                                                    10        20        30        40        50