Reactive sites of the 21-kD protein inhibitor of serine proteinases from potato tubers.
The effect of modifications of Met, Arg, and Lys residues on the inhibitory activity of a serine proteinase-inhibiting 21-kD protein from potato tubers has been studied. The data indicate that the 21-kD protein has two independent reactive sites for human leukocyte elastase (or chymotrypsin) and trypsin. It is concluded that the 21-kD inhibitor has Met and Arg residues in the P1 position of the reactive sites responsible for interactions with elastase (or chymotrypsin) and trypsin. It is shown that the 21-kD protein is capable of forming a triple complex binding simultaneously one molecule of trypsin and one molecule of chymotrypsin.
Valueva
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Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, 117071, Russia. inbio@glas.apc.org
Revina
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Mosolov
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D002851:Chromatography, High Pressure Liquid; D002918:Chymotrypsin / Q000037:antagonists & inhibitors; D006801:Humans; D007700:Kinetics; D019272:Leukocyte Elastase / Q000037:antagonists & inhibitors; D008970:Molecular Weight; D018517:Plant Roots / Q000737:chemistry; D015842:Serine Proteinase Inhibitors / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D011198:Solanum tuberosum / Q000737:chemistry*; D013379:Substrate Specificity; D014357:Trypsin / Q000378:metabolism
D015842:Serine Proteinase Inhibitors; D002918:Chymotrypsin; D019272:Leukocyte Elastase; D014357:Trypsin