Isolation and amino acid sequence of two trypsin isoinhibitors from duck pancreas

• Published in: Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology 1999-11, Vol.124 (3), p.281-288
• Main Authors: Wilimowska-Pelc, Anna, Olczak, Mariusz, Olichwier, Zofia, Gładysz, Marta, Wilusz, Tadeusz
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; amino acid sequences; Amino Acids - analysis; Anatidae; Animals; Chromatography, Affinity; Chromatography, High Pressure Liquid; Duck pancreas; Ducks; Electrophoresis, Polyacrylamide Gel; Freshwater; Kazal-type trypsin inhibitor; Molecular Sequence Data; Molecular Weight; Pancreas - chemistry; Peptides - chemistry; Peptides - isolation & purification; Peptides - metabolism; Protein Isoforms; Sequence Analysis, Protein; Serine Endopeptidases - metabolism; Species Specificity; trypsin inhibitors; Trypsin Inhibitors - chemistry; Trypsin Inhibitors - isolation & purification; Trypsin Inhibitors - metabolism; Trypsin Inhibitors - pharmacology
• ISSN: 1096-4959; 0305-0491; 1879-1107
• DOI: 10.1016/S0305-0491(99)00118-2

DPTI II and DPTI IV, two trypsin inhibitors from duck pancreas, have been isolated by affinity chromatography on immobilized anhydrotrypsin, anion exchange and RP-HPLC. The complete amino acid sequence of both inhibitors was determined after reductive carboxymethylation and digestion with Staphylococcus aureus V8 protease or trypsin. The inhibitors were each found to be a single polypeptide chain comprised of 69 amino acid residues and their molecular masses were estimated at 7687 Da for DPTI II and 7668 Da for DPTI IV. The only difference in amino acid sequence between the two inhibitors is the replacement of Arg for His residue in the C-terminal position of DPTI IV.