Navegando por Palavras-chave "human plasma kallikrein"
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- ItemSomente MetadadadosCharacterization of a Kunitz trypsin inhibitor with one disulfide bridge purified from Swartzia pickellii(Elsevier B.V., 2002-03-01) Cavalcanti, MDM; Oliva, MLV; Fritz, H.; Jochum, M.; Mentele, R.; Sampaio, M.; Coelho, LCBB; Batista, IFC; Sampaio, CAM; Universidade Federal de Pernambuco (UFPE); Univ Pernambuco; Universidade Federal de São Paulo (UNIFESP); Univ MunichSwartzia pickellii is a Leguminosae that belongs to the Caesalpinioideae sub-family the Swartzia pickellii Trypsin Inhibitor (SWTI), a serine proteinase inhibitor was isolated from its seeds. SWTI is a single polypeptide chain protein and it's structure has 174 amino acid residues, it homologous to other Kunitz plant inhibitors, however shows some major differences: it contains only one disulfide bridge, instead two which are usually found in plant Kunitz inhibitors, and the SWTI reactive site does not contain the usual Arg or Lys residues at the putative reactive site (position 65). A glycosylation site was detected at Asn38 with 1188 kDa carbohydrate portion. the primary structure micro heterogeneity was found combining the sequence determination and mass spectrometry. Three forms of SWTI were actually defined: two glycosylated forms a 20,204 kDa (Arg 165) and 20,185 kDa (His 165) and one deglycosylated form 19,016 kDa (Arg 165), all of them contain a Met residue at position 130. (C) 2002 Elsevier Science (USA).
- ItemSomente MetadadadosGlycosaminoglycans affect the action of human plasma kallikrein on kininogen hydrolysis and inflammation(Elsevier B.V., 2002-12-01) Andrezza, J. G.; Nunes, V. A.; Carmona, Adriana Karaoglanovic [UNIFESP]; Nader, Helena Bonciani [UNIFESP]; Dietrich, Carl Peter [UNIFESP]; Silveira, Vera Lucia Flor [UNIFESP]; Shimamoto, K.; Ura, N.; Sampaio, Misako Uemura [UNIFESP]; Sampaio, Claudio Augusto Machado [UNIFESP]; Araujo, M. S.; Universidade Federal de São Paulo (UNIFESP); Sapporo Med UnivHuman plasma kallikrein (huPK) is a serine proteinase involved in many biological processes including those of the kallikrein-kinin system. The action of huPK on kininogen results in bradykinin (BK) release, a potent mediator of inflammatory responses. BK generation may be influenced by several agents, and the aim of this work was to investigate the effect of glycosaminoglycans (GAGs) on human high-molecular-weight kininogen (HK) hydrolysis by huPK and on inflammation.huPK was pre-incubated in the absence and presence of different GAGs, followed by the addition of kininogen. Bradykinin released at different times was measured by radioimmunoassay, and K-M and k(cat) were calculated. Tuna and bovine dermatan sulfates, the most potent GAGs studied, reduced by 80% and 68%. respectively, the catalytic efficiency of huPK (control=4.1 x 10(4) M-1 s(-1)) in BK release.The effect of bovine dermatan sulfate (BDS) on inflammatory response was studied in rat paw edema induced by carrageenin and hourly determined (1-4 h) by plethysmography. BDS significantly reduced the inflammatory response in the first and second hours of measurements (24% and 28%, respectively), p < 0.05.GAGs were shown to reduce bradykinin release in vitro and in an inflammation model. This reduction may play a role in the control or maintenance of some pathological and physiological processes. (C) 2002 Published by Elsevier Science B.V.
- ItemSomente MetadadadosHuman plasma kallikrein and tissue kallikrein binding to a substrate based on the reactive site of a factor Xa inhibitor isolated from Bauhinia ungulata seeds(Elsevier B.V., 1999-12-01) Oliva, MLV; Andrade, S.; Batista, IFC; Sampaio, M. U.; Juliano, M.; Fritz, H.; Auerswald, E. A.; Sampaio, CAM; Universidade Federal de São Paulo (UNIFESP); Univ MunichKunitz type Bauhinia ungulata factor Xa inhibitor (BuXI) was purified from B. ungulata seeds. BuXI inactivates factor Xa and human plasma kallikrein (HuPK) with K-i values of 18.4 and 6.9 nM, respectively. However, Bauhinia variegata trypsin inhibitor (BvTI) which is 70% homologous to BuXI does not inhibit factor Xa and is less efficient on HuPK (K-i = 80 nM). the comparison between BuXI and BvTI reactive site structure indicates differences at Met(59), Thr(66) and Met(67) residues. the hydrolysis rate of quenched fluorescence peptide substrates based on BuXI reactive site sequence, Abz-VMIAALPRTMFIQ-EDDnp (leading peptide), by HuPK and porcine pancreatic kallikrein (PoPK) is low, but hydrolysis is enhanced with Abz-VMIAALPRTMQ-EDDnp, derived from the leading peptide shortened by removing the dipeptide Phe-Ileu from the C-terminal portion, for HuPK (K-m = 0.68 mu M, k(cat)/K-m = 1.3 X 10(6) M-1 s(-1)), and the shorter substrate Abz-LPRTMQ-EDDnp is better for PoPK (K-m = 0.66 mu M, k(cat)/K-m = 2.2 X 10(3) M-1 s(-1)). the contribution of substrate methionine residues to HuPK and PoPK hydrolysis differs from that observed with factor Xa. the determined K-m and k(cat) values suggest that the substrates interact with kallikreins the same as an enzyme and inhibitor interacts to form complexes. (C) 1999 Elsevier Science B.V. All rights reserved.
- ItemSomente MetadadadosPrimary sequence determination of a Kunitz inhibitor isolated from Delonix regia seeds(Elsevier B.V., 2001-07-01) Pando, S. C.; Oliva, MLV; Sampaio, CAM; Di Ciero, L.; Novello, J. C.; Marangoni, S.; Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Campinas (UNICAMP)A serine proteinase inhibitor was purified from Delonix regia seeds a Leguminosae tree of the Caesalpinioideae subfamily. the inhibitor named DrTI, inactivated trypsin and human plasma kallikrein with K-i values 2.19x10(-8) M and 5.25 nM, respectively. Its analysis by SDS-PAGE 10-20% showed that the inhibitor is a protein with a single polypeptide chain of M-r 22 h Da. the primary sequence of the inhibitor was determined by Edman degradation, thus indicating that it contained 185 amino acids and showed that it belongs to the Kunitz type family; however, its reactive site did not contain Arg or Lys at the putative reactive site (position 63, SbTI numbering) or it was displaced when compared to other Kunitz-type inhibitors. (C) 2001 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosPurification, characterization, and cloning of a serine proteinase inhibitor from the ectoparasite Haematobia irritans irritans (Diptera : Muscidae)(Elsevier B.V., 2004-03-01) Azzolini, S. S.; Santos, JMC; Souza, A. F.; Torquato, RJS; Hirata, I. Y.; Andreotti, R.; Tanaka, A. S.; Universidade Federal de São Paulo (UNIFESP); Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)The fly Haematobia irritans irritant is one of the most important ectoparasites in cattle production, due to, its ability to suck large amounts of blood. This report describes the purification and characterization of a serine proteinase inhibitor (HiTI) present in H. i. irritans head and thorax extracts. the HiTI purified by, affinity chromatography on trypsin-Sepharose has a molecular mass of 7029 Da by MALDI-TOF mass spectrometry. HiTI inhibited bovine trypsin, human neutrophil elastase, and a trypsin-like enzyme, purified from H. i. irritans abdomen with dissociation constants of 0.57, 1.30, and 0.20 nM, respectively. the HiTI partial amino acid sequence allowed its classification into the BPTI-Kunitz-type family. An HiTI cDNA fragment was cloned in the pGEMT vector using RT-PCR. the translated amino acid sequence of HiTI cDNA confirmed a unique Kunitz-type-domain protein. Our results suggest that HiTI could control some endogenous enzyme, e.g., the H. i. irritans trypsin-like protein. (C) 2004 Elsevier Inc. All rights reserved.