Cationic inhibitors of serine proteinases from buckwheat seeds.
Preparations of low molecular weight protein inhibitors of serine proteinases have been obtained from buckwheat (Fagopyrum esculentum) seeds by chromatography of seed extract on trypsin-Sepharose 4B, Mono-Q, and Mono-S ion exchangers (FPLC regime). Their molecular masses, determined by mass spectrometry, were 5203 (BWI-1c), 5347 (BWI-2c), 7760 (BWI-3c), and 6031 daltons (BWI-4c). All of the inhibitors possess high pH- and thermal stability in the pH range 2-12. In addition to trypsin, BWI-3c and BWI-4c inhibited chymotrypsin and subtilisin-like bacterial proteases. The N-terminal sequences of all of the inhibitors were determined: BWI-1c (23 residues), BWI-2c (33 residues), BWI-3c (18 residues), and BWI-4c (20 residues). In their physicochemical properties and N-terminal amino acid sequences, the buckwheat seed trypsin inhibitors BWI-3c and BWI-4c appear to belong to potato proteinase inhibitor I family.
Tsybina
T A
TA
Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119899 Russia.
Dunaevsky
Y E
YE
Musolyamov
A K
AK
Egorov
T A
TA
Belozersky
M A
MA
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D002412:Cations; D002846:Chromatography, Affinity; D002918:Chymotrypsin / Q000037:antagonists & inhibitors; D019612:Fagopyrum / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010455:Peptides / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D010940:Plant Proteins; D012639:Seeds / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D015842:Serine Proteinase Inhibitors / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D013381:Subtilisins / Q000037:antagonists & inhibitors; D014357:Trypsin / Q000187:drug effects
D000596:Amino Acids; C448307:BWI 3c peptide, Fagopyrum esculentum; C448306:BWI 4c peptide; D002412:Cations; D010455:Peptides; D010940:Plant Proteins; D015842:Serine Proteinase Inhibitors; D013381:Subtilisins; D002918:Chymotrypsin; D014357:Trypsin