Design of kallidin-releasing tissue kallikrein inhibitors based on the specificities of the enzyme's binding subsites.
The tissue kallikrein inhibitors reported in the present work were derived by selectively replacing residues in Nalpha-substituted arginine- or phenylalanine-pNA (where pNA is p-nitroanilide), and in peptide substrates for these enzymes. Phenylacetyl-Arg-pNA was found to be an efficient inhibitor of human tissue kallikrein (Ki 0.4 microM) and was neither a substrate nor an inhibitor of plasma kallikrein. The peptide inhibitors having phenylalanine as the P1 residue behaved as specific inhibitors for kallidin-releasing tissue kallikreins, while plasma kallikrein showed high affinity for inhibitors containing (p-nitro)phenylalanine at the same position. The Ki value of the most potent inhibitor developed, Abz-Phe-Arg-Arg-Pro-Arg-EDDnp [where Abz is o-aminobenzoyl and EDDnp is N-(2,4-dinitrophenyl)-ethylenediamine], was 0.08 microM for human tissue kallikrein. Progress curve analyses of the inhibition of human tissue kallikrein by benzoyl-Arg-pNA and phenylacetyl-Phe-Ser-Arg-EDDnp indicated a single-step mechanism for reversible formation of the enzyme-inhibitor complex.
Portaro
F C
FC
Department of Biophysics, Universidade Federal de São Paulo-Escola Paulista de Medicina, Rua Três de Maio 100, São Paulo 04044-020, Brazil.
Cezari
M H
MH
Juliano
M A
MA
Juliano
L
L
Walmsley
A R
AR
Prado
E S
ES
D001587:Benzoylarginine-2-Naphthylamide / Q000031:analogs & derivatives / Q000494:pharmacology; D006801:Humans; D007609:Kallidin / Q000378:metabolism*; D007610:Kallikreins / Q000037:antagonists & inhibitors*; D007700:Kinetics; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology; D020840:Tissue Kallikreins; D014662:Vasoconstrictor Agents / Q000037:antagonists & inhibitors*
D010455:Peptides; D014662:Vasoconstrictor Agents; D001587:Benzoylarginine-2-Naphthylamide; D007609:Kallidin; D007610:Kallikreins; D020840:Tissue Kallikreins