Kinetics of interaction of trypsin with an anionic inhibitor of trypsin BWI-1a from buckwheat seeds.
The kinetics of binding of bovine trypsin to a proteinaceous inhibitor of trypsin from buckwheat seeds (BWI-1a) has been studied. The association rate constant (k(ass)) was 2.2 x 10(6) M-1 x sec-1 and the dissociation rate constant (k(off)) of the enzyme--inhibitor complex was 3.5 x 10(-3) sec-1; the inhibition constant Ki was 1.5 nM. The inhibitor BWI-1a is of the slow, tightly binding type. The mechanism of the inhibition of bovine trypsin by the trypsin inhibitor BWI-1a was studied. The mechanism of inhibition was found to involve two steps according to the kinetic data.
Gladysheva
I P
IP
School of Chemistry, Lomonosov Moscow State University, Moscow, 119899, Russia. LAR_LAB@ENZYME.CHEM.MSU.RU
Gladyshev
D P
DP
Dunaevsky
Y E
YE
Belozersky
M A
MA
Larionova
N I
NI
D000818:Animals; D000838:Anions; D002417:Cattle; D019612:Fagopyrum / Q000378:metabolism*; D007700:Kinetics; D010940:Plant Proteins / Q000302:isolation & purification / Q000378:metabolism*; D014357:Trypsin / Q000378:metabolism*; D014361:Trypsin Inhibitors / Q000302:isolation & purification / Q000378:metabolism*
D000838:Anions; C095816:BWI-1 protein, Fagopyrum esculentum; D010940:Plant Proteins; D014361:Trypsin Inhibitors; D014357:Trypsin