Primary structure of cathepsin D inhibitor from potatoes and its structure relationship to soybean trypsin inhibitor family.
A novel effective procedure for the purification of cathepsin D inhibitor from potatoes (PDI) was developed. The amino acid sequence of PDI was determined by analysis of the cyanogen bromide digest and of the limited tryptic and chymotryptic digest of the protein. The inhibitor is a single polypeptide chain protein consisting of 188 residues with a simple sugar moiety attached to Asn-19. The tentative disulfide pairings are also suggested. The sequence data clearly indicate that PDI is homologous with the soybean trypsin inhibitor (STI) (Kunitz) family. The active center of PDI for trypsin inhibition was identified as Pro-Val-Arg-Phe in analogy to STI.
Mares
M
M
Institute of Organic Chemistry, Czechoslovak Academy of Sciences, Prague, Czechoslovakia.
Meloun
B
B
Pavlik
M
M
Kostka
V
V
Baudys
M
M
D000595:Amino Acid Sequence; D002402:Cathepsin D / Q000037:antagonists & inhibitors*; D008969:Molecular Sequence Data; D010940:Plant Proteins; D011480:Protease Inhibitors / Q000302:isolation & purification; D011506:Proteins / Q000302:isolation & purification; D011198:Solanum tuberosum / Q000201:enzymology*; D014360:Trypsin Inhibitor, Kunitz Soybean; D014361:Trypsin Inhibitors
D010940:Plant Proteins; D011480:Protease Inhibitors; D011506:Proteins; D014361:Trypsin Inhibitors; C060481:CDI protein, Solanum tuberosum; D014360:Trypsin Inhibitor, Kunitz Soybean; D002402:Cathepsin D