Bibliografie tematiche / Cysteine protease inhibitor

Indice

Articoli di riviste
Tesi
Libri
Capitoli di libri
Atti di convegni
Rapporti di organizzazioni

Letteratura scientifica selezionata sul tema "Cysteine protease inhibitor"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 5 febbraio 2022

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili

Scegli il tipo di fonte:

Consulta la lista di attuali articoli, libri, tesi, atti di convegni e altre fonti scientifiche attinenti al tema "Cysteine protease inhibitor".

Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.

Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.

Articoli di riviste sul tema "Cysteine protease inhibitor"

Mitchell, Angela M., e R. Jude Samulski. "Mechanistic Insights into the Enhancement of Adeno-Associated Virus Transduction by Proteasome Inhibitors". Journal of Virology 87, n. 23 (11 settembre 2013): 13035–41. http://dx.doi.org/10.1128/jvi.01826-13.

Testo completo

Abstract (sommario):

Proteasome inhibitors (e.g., bortezomib, MG132) are known to enhance adeno-associated virus (AAV) transduction; however, whether this results from pleotropic proteasome inhibition or off-target serine and/or cysteine protease inhibition remains unresolved. Here, we examined recombinant AAV (rAAV) effects of a new proteasome inhibitor, carfilzomib, which specifically inhibits chymotrypsin-like proteasome activity and no other proteases. We determined that proteasome inhibitors act on rAAV through proteasome inhibition and not serine or cysteine protease inhibition, likely through positive changes late in transduction.

Gli stili APA, Harvard, Vancouver, ISO e altri

Dubin, G., J. Stec-Niemczyk, T. Dylag, J. Silberring, A. Dubin e J. Potempa. "Characterisation of a highly specific, endogenous inhibitor of cysteine protease from Staphylococcus epidermidis, a new member of the staphostatin family". Biological Chemistry 385, n. 6 (7 giugno 2004): 543–46. http://dx.doi.org/10.1515/bc.2004.064.

Testo completo

Abstract (sommario):

AbstractStaphostatins, a novel family of cysteine protease inhibitors with a unique mechanism of action and distinct protein fold has recently been discovered. In this report we describe the properties ofStaphylococcus epidermidisstaphostatin A (EcpB), a new member of the family. As for other staphostatins, the recombinantS. epidermidisstaphostatin A exerted very narrow inhibitory specificity, limited to cysteine protease from the same species. The closely related proteases fromS. aureuscleaved the inhibitor at the reactive site peptide bond and inactivated it. The EcpB homologue,S. aureusstaphostatin A (ScpB), was also susceptible to proteolytic cleavage at the same site by nontarget cysteine proteases. Conversely,S. aureusstaphostatin B (SspC) was resistant to such proteolysis. The difference in the susceptibility of individual inhibitors to proteolytic cleavage at the reactive site suggests subtle variations in the mechanism of interaction with cysteine proteases.

Gli stili APA, Harvard, Vancouver, ISO e altri

Tušar, Livija, Aleksandra Usenik, Boris Turk e Dušan Turk. "Mechanisms Applied by Protein Inhibitors to Inhibit Cysteine Proteases". International Journal of Molecular Sciences 22, n. 3 (20 gennaio 2021): 997. http://dx.doi.org/10.3390/ijms22030997.

Testo completo

Abstract (sommario):

Protein inhibitors of proteases are an important tool of nature to regulate and control proteolysis in living organisms under physiological and pathological conditions. In this review, we analyzed the mechanisms of inhibition of cysteine proteases on the basis of structural information and compiled kinetic data. The gathered structural data indicate that the protein fold is not a major obstacle for the evolution of a protease inhibitor. It appears that nature can convert almost any starting fold into an inhibitor of a protease. In addition, there appears to be no general rule governing the inhibitory mechanism. The structural data make it clear that the “lock and key” mechanism is a historical concept with limited validity. However, the analysis suggests that the shape of the active site cleft of proteases imposes some restraints. When the S1 binding site is shaped as a pocket buried in the structure of protease, inhibitors can apply substrate-like binding mechanisms. In contrast, when the S1 binding site is in part exposed to solvent, the substrate-like inhibition cannot be employed. It appears that all proteases, with the exception of papain-like proteases, belong to the first group of proteases. Finally, we show a number of examples and provide hints on how to engineer protein inhibitors.

Gli stili APA, Harvard, Vancouver, ISO e altri

Sallai, Roberto Carlos, Bruno Ramos Salu, Rosemeire Aparecida Silva-Lucca, Flávio Lopes Alves, Thiago Henrique Napoleão, Patrícia Maria Guedes Paiva, Rodrigo da Silva Ferreira, Misako Uemura Sampaio e Maria Luiza Vilela Oliva. "Biotechnological Potential of Araucaria angustifolia Pine Nuts Extract and the Cysteine Protease Inhibitor AaCI-2S". Plants 9, n. 12 (30 novembre 2020): 1676. http://dx.doi.org/10.3390/plants9121676.

Testo completo

Abstract (sommario):

Protease inhibitors are involved in the regulation of endogenous cysteine proteases during seed development and play a defensive role because of their ability to inhibit exogenous proteases such as those present in the digestive tracts of insects. Araucaria angustifolia seeds, which can be used in human and animal feed, were investigated for their potential for the development of agricultural biotechnology and in the field of human health. In the pine nuts extract, which blocked the activities of cysteine proteases, it was detected potent insecticidal activity against termites (Nasutitermes corniger) belonging to the most abundant termite genus in tropical regions. The cysteine inhibitor (AaCI-2S) was purified by ion-exchange, size exclusion, and reversed-phase chromatography. Its functional and structural stability was confirmed by spectroscopic and circular dichroism studies, and by detection of inhibitory activity at different temperatures and pH values. Besides having activity on cysteine proteases from C. maculatus digestive tract, AaCI-2S inhibited papain, bromelain, ficin, and cathepsin L and impaired cell proliferation in gastric and prostate cancer cell lines. These properties qualify A. angustifolia seeds as a protein source with value properties of natural insecticide and to contain a protease inhibitor with the potential to be a bioactive molecule on different cancer cells.

Gli stili APA, Harvard, Vancouver, ISO e altri

Cornwall, Gail A., Angus Cameron, Iris Lindberg, Daniel M. Hardy, Nathaly Cormier e Nelson Hsia. "The Cystatin-Related Epididymal Spermatogenic Protein Inhibits the Serine Protease Prohormone Convertase 2". Endocrinology 144, n. 3 (1 marzo 2003): 901–8. http://dx.doi.org/10.1210/en.2002-220997.

Testo completo

Abstract (sommario):

The cystatin-related epididymal spermatogenic (CRES) protein is related to the family 2 cystatins of the cystatin superfamily of cysteine protease inhibitors. However, CRES lacks sequences important for cysteine protease inhibitory activity and is specifically expressed in reproductive and neuroendocrine tissues. Thus, CRES is distinct from cystatins and may perform unique tissue-specific functions. The purpose of the present study was to determine whether CRES functions as a protease inhibitor in in vitro assays. In contrast to mouse recombinant cystatin C, recombinant CRES did not inhibit the cysteine proteases papain and cathepsin B, suggesting that it probably does not function as a typical cystatin. CRES, however, inhibited the serine protease prohormone convertase 2 (PC2), a protease involved in prohormone processing in the neuroendocrine system, whereas cystatin C showed no inhibition. CRES did not inhibit subtilisin, trypsin, or the convertase family members, PC1 and furin, indicating that it selectively inhibits PC2. Kinetic analysis showed that CRES is a competitive inhibitor of PC2 with a Ki of 25 nm. The removal of N-terminal sequences from CRES decreased its affinity for PC2, suggesting that the N terminus may be important for CRES to function as an inhibitor. These studies suggest that CRES is a cross-class inhibitor that may regulate proprotein processing within the reproductive and neuroendocrine systems.

Gli stili APA, Harvard, Vancouver, ISO e altri

Van Wyk, S. G., K. J. Kunert, B. J. Vorster e U. Schluter. "Interaction of cysteine protease inhibitor mutants with cysteine proteases". South African Journal of Botany 76, n. 2 (aprile 2010): 406. http://dx.doi.org/10.1016/j.sajb.2010.02.053.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Parikh, Sunil, Jun Liu, Puran Sijwali, Jiri Gut, Daniel E. Goldberg e Philip J. Rosenthal. "Antimalarial Effects of Human Immunodeficiency Virus Type 1 Protease Inhibitors Differ from Those of the Aspartic Protease Inhibitor Pepstatin". Antimicrobial Agents and Chemotherapy 50, n. 6 (giugno 2006): 2207–9. http://dx.doi.org/10.1128/aac.00022-06.

Testo completo

Abstract (sommario):

ABSTRACT Human immunodeficiency virus type 1 protease inhibitors (HIVPIs) and pepstatin are aspartic protease inhibitors with antimalarial activity. In contrast to pepstatin, HIVPIs were not synergistic with a cysteine protease inhibitor or more active against parasites with the cysteine protease falcipain-2 knocked out than against wild-type parasites. As with pepstatin, HIVPIs were equally active against wild-type parasites and against parasites with the food vacuole plasmepsin aspartic proteases knocked out. The antimalarial mechanism of HIVPIs differs from that of pepstatin.

Gli stili APA, Harvard, Vancouver, ISO e altri

Bevec, T., V. Stoka, G. Pungercic, I. Dolenc e V. Turk. "Major histocompatibility complex class II-associated p41 invariant chain fragment is a strong inhibitor of lysosomal cathepsin L." Journal of Experimental Medicine 183, n. 4 (1 aprile 1996): 1331–38. http://dx.doi.org/10.1084/jem.183.4.1331.

Testo completo

Abstract (sommario):

The invariant chain (Ii) is associated with major histocompatibility complex class II molecules during early stages of their intracellular transport. In an acidic endosomal/lysosomal compartment, it is proteolytically cleaved and removed from class II heterodimers. Participation of aspartic and cysteine proteases has been observed in in vitro degradation of Ii, but the specific enzymes responsible for its in vivo processing are as yet undefined. We have previously isolated a noncovalent complex of the lysosomal cysteine protease cathepsin L with a peptide fragment derived from the p41 form of Ii from human kidney. Here we show that this Ii fragment, which is identical to the alternatively spliced segment of p41, is a very potent competitive inhibitor of cathepsin L (equilibrium inhibition constant Ki = 1.7 X 10(-12) M). It inhibits two other cysteine proteases, cathepsin H and papain, but to much lesser extent. Cysteine proteases cathepsins B, C, and S, as well as representatives of serine, aspartic, and metalloproteases, are not inhibited at all. These findings suggest a novel role for p41 in the regulation of various proteolytic activities during antigen processing and presentation. The Ii inhibitory fragment shows no sequence homology with the known cysteine protease inhibitors, and may, therefore, represent a new class.

Gli stili APA, Harvard, Vancouver, ISO e altri

Monteiro, Ana C. S., Magnus Abrahamson, Ana P. C. A. Lima, Marcos A. Vannier-Santos e Julio Scharfstein. "Identification, characterization and localization of chagasin, a tight-binding cysteine protease inhibitor inTrypanosoma cruzi". Journal of Cell Science 114, n. 21 (1 novembre 2001): 3933–42. http://dx.doi.org/10.1242/jcs.114.21.3933.

Testo completo

Abstract (sommario):

Lysosomal cysteine proteases from mammalian cells and plants are regulated by endogenous tight-binding inhibitors from the cystatin superfamily. The presence of cystatin-like inhibitors in lower eukaryotes such as protozoan parasites has not yet been demonstrated, although these cells express large quantities of cysteine proteases and may also count on endogenous inhibitors to regulate cellular proteolysis. Trypanosoma cruzi, the causative agent of Chagas’ heart disease, is a relevant model to explore this possibility because these intracellular parasites rely on their major lysosomal cysteine protease (cruzipain) to invade and multiply in mammalian host cells. Here we report the isolation, biochemical characterization, developmental stage distribution and subcellular localization of chagasin, an endogenous cysteine protease inhibitor in T. cruzi. We used high temperature induced denaturation to isolate a heat-stable cruzipain-binding protein (apparent molecular mass, 12 kDa) from epimastigote lysates. This protein was subsequently characterized as a tight-binding and reversible inhibitor of papain-like cysteine proteases. Immunoblotting indicated that the expression of chagasin is developmentally regulated and inversely correlated with that of cruzipain. Gold-labeled antibodies localized chagasin to the flagellar pocket and cytoplasmic vesicles of trypomastigotes and to the cell surface of amastigotes. Binding assays performed by probing living parasites with fluorescein (FITC)-cruzipain or FITC-chagasin revealed the presence of both inhibitor and protease at the cell surface of amastigotes. The intersection of chagasin and cruzipain trafficking pathways may represent a checkpoint for downstream regulation of proteolysis in trypanosomatid protozoa.

Gli stili APA, Harvard, Vancouver, ISO e altri

Lee, Jung-Yub, Su-Min Song, Eun-Kyung Moon, Yu-Ran Lee, Bijay Kumar Jha, Dinzouna-Boutamba Sylvatrie Danne, Hee-Jae Cha et al. "Cysteine Protease Inhibitor (AcStefin) Is Required for Complete Cyst Formation of Acanthamoeba". Eukaryotic Cell 12, n. 4 (8 febbraio 2013): 567–74. http://dx.doi.org/10.1128/ec.00308-12.

Testo completo

Abstract (sommario):

ABSTRACTThe encystation ofAcanthamoebaleads to the formation of resilient cysts from vegetative trophozoites. This process is essential for parasite survival under unfavorable conditions, such as those associated with starvation, low temperatures, and biocides. Furthermore, cysteine proteases have been implicated in the massive turnover of intracellular components required for encystation. Thus, strict modulation of the activities of cysteine proteases is required to protectAcanthamoebafrom intracellular damage. However, mechanisms underlying the control of protease activity during encystation have not been established inAcanthamoeba. In the present study, we identified and characterizedAcanthamoebacysteine protease inhibitor (AcStefin), which was found to be highly expressed during encystation and to be associated with lysosomes by fluorescence microscopy. Recombinant AcStefin inhibited various cysteine proteases, including human cathepsin B, human cathepsin L, and papain. Transfection with small interfering RNA against AcStefin increased cysteine protease activity during encystation and resulted in incomplete cyst formation, reduced excystation efficiency, and a significant reduction in cytoplasmic area. Taken together, these results indicate that AcStefin is involved in the modulation of cysteine proteases and that it plays an essential role during the encystation ofAcanthamoeba.

Gli stili APA, Harvard, Vancouver, ISO e altri

Più fonti

Tesi sul tema "Cysteine protease inhibitor"

Chen, Hongyuan. "Development of macrocyclic β-strand calpain cysteine protease inhibitors". Thesis, University of Canterbury. Chemistry, 2011. http://hdl.handle.net/10092/5582.

Testo completo

Abstract (sommario):

The work in this thesis reports studies directed to developing a calpain cysteine protease inhibitor that could be of value in slowing cataract development in humans. The work focuses on the development of macrocyclic compounds which can have advantages over acyclic compounds due to their resistance to proteolytic hydrolysis, improved selectivity, bioavailability and membrane permeability. A review of X-ray crystal structures of natural and synthetic calpain inhibitors complexed with the cysteine protease calpain show the inhibitors generally bind in the enzyme active site in an extended β-strand conformation. The calpain inhibitor SJA-6017 has been identified as a suitable lead compound. The importance of the para-fluoro group in SJA-6017 has been investigated. Modifications have been made to constrain this basic structure within a macrocycle and restrict the peptide chain as a β-strand conformation. Macrocycle CAT811 is a potent calpain 1 and 2 inhibitor and shows promise in slowing the progression of cortical cataract in trials with sheep having a hereditary propensity towards the development of cataract. In this thesis I report studies directed to improve the yield of the key RCM macrocyclisation step in the synthesis of aldehyde CAT811 and of three ester analogues (2.1, 2.3 and 2.4). I also report the development of a more commercial route to CAT811 not involving RCM but using intramolecular nucleophilic cyclisation. This intramolecular nucleophilic cyclisation strategy was attempted for the preparation of a histidine containing macrocyclic ester (4.1a) but was unsuccessful. An alternate strategy involving intramolecular lactamization proved successful for the synthesis of histidine-based macrocyclic esters (4.1a-4.3a). Reduction to the corresponding alcohols (4.1b-4.3b) was successful and oxidation of (4.1b and 4.3b) afforded the corresponding aldehydes (4.1c and 4.3c) for biological assay against ovine calpain 2. Aldehyde 4.3c has an IC50 of 1 μM and the corresponding alcohol 4.3b shows no activity (IC50 > 50 μM) consistent with the modelling which indicated that these two compounds did not adopt a β-strand conformation in the docking studies. Aldehyde 4.1c, on the other hand, shows significant inhibitory activity with an IC50 of 238 nM but as expected the corresponding alcohol 4.1b shows little activity (IC50 = 29 μM). Modelling studies showed that both the aldehyde 4.1c and the alcohol 4.1b on docking can form a β-strand with appropriate H-bonding interactions. The aldehyde is more active than the alcohol due to the reactivity of the aldehyde warhead allowing for the reversible formation of a hemiacetal. A similar difference in reactivity is observed for CAT811 (30 nM) and its alcohol analogue (700 nM). These results demonstrate the value of molecular modelling as a screening mechanism before unproductive synthetic work is considered.

Gli stili APA, Harvard, Vancouver, ISO e altri

Musonda, Chitalu Christopher. "Antimalarial and cysteine protease inhibitor pharmacophores as scaffolds for new antimalarial agents". Doctoral thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/11811.

Testo completo

Abstract (sommario):

Includes bibliographical references.
The work in this thesis is threefold: (i) A new series of antiplasmodial agents were initially designed based on the β-amino alcohol bioactiphore, a subunit that is found in a number of antimalarial agents. (ii) Various thiosemicarbozones and semicarbozones were designed and synthesized as potential mechanism-based inhibiotrs of parasitic cysteine proteases. (iii) Multicomponenet reactions offer the advantage of introducing chemical diversity in fewer steps than conventional multi step organic synthesis. New chloroquine-type compounds were designed and synthesized using the Ugi 4 component condensation reaction and its variants. The synthesized compounds ranged from simple peptidic molecules to rigid heterocycles.

Gli stili APA, Harvard, Vancouver, ISO e altri

Vindebro, Reine. "Studies on secreted cysteine proteases of Streptococcus pyogenes : IdeS and SpeB". Doctoral thesis, Umeå universitet, Institutionen för molekylärbiologi (Medicinska fakulteten), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-88223.

Testo completo

Abstract (sommario):

The pathogen Streptococcus pyogenes is a significant cause of human morbidity and mortality. Most of the work in this thesis is focused on streptococcal virulence factor IdeS, but the thesis also features work on SpeB, another streptococcal virulence factor. Both IdeS and SpeB are secreted cysteine proteases and both have previously been shown to degrade human IgG. IgG is the only known substrate for IdeS while SpeB is a more promiscuous protease with a larger number of identified substrates. A significant part of the data presented in this thesis is the result of designing and optimizing methods to detect and accurately measure the proteolytic degradation of IgG. Methods aimed at measuring the binding interactions between enzyme and substrate have also been frequently utilized. I show that IdeS is a monomeric protease, as opposed to previously published data that suggested it to be dimeric. IdeS cleaves the two heavy chains of IgG in a two-step reaction and I demonstrate that the first cleavage is magnitudes faster than the second one. This means that IdeS is a more efficient enzyme than previously thought. The difference in rate cannot completely be explained by a loss of affinity between IdeS and IgG after the cleavage of the first heavy chain. The velocity of IdeS is further increased by the presence of human Cystatin C, via an unknown mechanism. Cystatin C is normally a protease inhibitor and it having an opposite effect is puzzling.The synthesis and evaluation of novel inhibitors are also described. Peptide analogues mimicking the sequence surrounding the scissile bond on IgG - with an amino acid replaced with a more rigid motif - act as specific, but low-affinity, inhibitors of IdeS. The peptide analogues’ inhibitory capacity for SpeB and papain was also assayed.When it comes to SpeB, I show that it does not have IgG as a substrate under physiological conditions, in contrast to what was previously thought. This thesis does not only present findings on the IgG degrading capacity of IdeS and SpeB but also include data on fundamental enzymatic properties for these proteases.

Gli stili APA, Harvard, Vancouver, ISO e altri

James, Karen Amanda Ellis. "Design, synthesis, and evaluation of novel cysteine protease inhibitors". Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/30283.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Friedrich, Beate. "Cathepsine B, H, L und ihre Inhibitoren im Gewebe und in Zellkulturen der Prostata". Doctoral thesis, [S.l.] : [s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=957675186.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Pol, Ewa. "Mechanism of interaction of the mammalian cysteine protease inhibitors, cystatin A and B, with target proteases /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-5927-3.pdf.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Leung, Donmienne Doen Mun. "Studies of serine and cysteine protease inhibitors /". St. Lucia, Qld, 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16491.pdf.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Ovat, Asli. "Design, synthesis and evaluation of cysteine protease inhibitors". Diss., Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/33822.

Testo completo

Abstract (sommario):

Cysteine proteases are important drug targets due to their involvement in many biological processes such as protein turnover, digestion, blood coagulation, apoptosis, cell differentiation, cell signaling, and the immune response. In this thesis, we have reported the design, synthesis and evaluation of clan CA and clan CD cysteine protease inhibitors. Aza-peptidyl Michael acceptor and epoxide inhibitors for asparaginyl endopeptidases (legumains) from the bloodfluke, Schistosoma mansoni (SmAE) and the hard tick, Ixodes ricinus (IrAE) were designed and synthesized. SARs were similar, but with some notable exceptions. Both enzymes prefer disubstituted amides to monosubstituted amides in the P1' position and potency increased as we increased the hydrophobicity of the inhibitor in this position. Extending the inhibitor to P5 resulted in increased inhibitory potency, especially against IrAE, and both enzymes prefer small over large hydrophobic residues in the P2 position. Aza-peptide Michael acceptor inhibitors are more potent than aza-peptide epoxide inhibitors and, for some of these compounds, second order inhibition rate constants are the fastest yet discovered. We have also synthesized aza-peptidyl Michael acceptor and epoxide inhibitors for the parasitic cysteine proteases; cruzain, rhodesain. We have found that monosubstituted amides were favored over disubstituted amides indicating the involvement of the amide hydrogen in a H-bond network. We have shown that aza-peptide epoxides were as potent as Michael acceptors and we have obtained compounds with IC50 values as low as 20 nM. We have worked on the synthesis of heterocyclic peptidyl α-ketoamides, peptidyl ketones and aza-peptidyl ketones as calpain inhibitors. We have synthesized peptidyl α-ketoamides with nucleotide bases in the primed region to create compounds that can cross the blood-brain barrier. We have improved the potency by introducing a hydrophobic group on the adenine ring. We have obtained compounds with Ki values in the nanomolar range. We have designed peptidyl aminoketones as a new class of inhibitors for calpain. Peptidyl aminoketones were less potent than peptidyl α-ketoamides but still reasonable inhibitors of calpain that have the potential to cross the BBB.

Gli stili APA, Harvard, Vancouver, ISO e altri

Mehrtens, (nee Nikkel) Janna Marie. "The Design, Synthesis and Biological Assay of Cysteine Protease Specific Inhibitors". Thesis, University of Canterbury. Chemistry, 2007. http://hdl.handle.net/10092/3271.

Testo completo

Abstract (sommario):

This thesis investigates the design, synthesis and biological assay of cysteine protease inhibitors within the papain superfamily of cysteine proteases. This is achieved by examining the effect of inhibitor design, especially warheads, on IC₅₀ values and structureactivity relationships between cysteine protease inhibitors of the papain superfamily. The representative proteases used are m-calpain, μ-calpain, cathepsin B and papain. Chapter One is an introductory chapter; Chapters Two-Four describe the design and synthesis of cysteine protease inhibitors; Chapter Five discusses assay protocol; and Chapter Six contains the assay results and structure-activity relationships of the synthesised inhibitors. Chapter One introduces cysteine proteases of the papain family and examines the structure, physiology and role in disease of papain, cathepsin B, m-calpain and μ-calpain. The close structural homology that exists between these members of the papain superfamily is identified, as well characteristics unique to each protease. Covalent reversible, covalent irreversible and non-covalent warheads are defined. The generic inhibitor scaffold of address region, recognition and warhead, upon which the inhibitors synthesised in this thesis are based, is also introduced. Chapter Two introduces reversible cysteine protease inhibitors found in the literature and that little is known about the effect of inhibitor warhead on selectivity within the papain superfamily. Oxidation of the dipeptidyl alcohols 2.6, 2.26, 2.29, 2.30, 2.35 and 2.36 utilising the sulfur trioxide-pyridine complex gave the aldehydes 2.3, 2.27, 2.19, 2.2, 2.21 and 2.22. Semicarbazones 2.37-2.40 were synthesised by a condensation reaction between the alcohol 2.3 and four available semicarbazides. The amidoximes 2.48 and 2.49 separately underwent thermal intramolecular cyclodehydration to give the 3-methyl-1,2,4- oxadiazoles 2.41 and 2.50. The aldehydes 2.3 and 2.27 were reacted with potassium cyanide to give the cyanohydrins 2.51 and 2.52. The cyanohydrins 2.51 and 2.52 were separately reacted to give 1) the α-ketotetrazoles 2.43 and 2.55; 2) the α-ketooxazolines 2.42 and 2.58; 3) the esterified cyanohydrins 2.60 and 2.61. A two step SN2 displacement reaction of the alcohol 2.6 to give the azide 2.62, an example of a non-covalent cysteine protease inhibitor. Chapter Three introduces inhibitors with irreversible warheads. The well-known examples of epoxysuccinic acids 3.1 and 3.5 are discussed in detail, highlighting the lack of irreversible cysteine protease specific inhibitors. The aldehydes 2.3 and 2.27 were reacted under Wittig conditions to give the α,β-unsaturated carbonyls 3.14-3.18. Horner- Emmons-Wadsworth methodology was utilised for the synthesis of the vinyl sulfones 3.20- 3.23. The dipeptidyl acids 2.24 and 2.28 were separately reacted with diazomethane to give the diazoketones 3.25 and 3.26. The diazoketones 3.25 and 3.26 were separately reacted with hydrogen bromide in acetic acid (33%) to give the α-bromomethyl ketones 3.27 and 3.28, which were subsequently reduced to give the α-bromomethyl alcohols 3.29-3.32. Under basic conditions the α-bromomethyl alcohols 3.29-3.32 ring-closed to form the peptidyl epoxides 3.33-3.36. Chapter Four introduces the disadvantages of peptide-based inhibitors. A discussion is given on the benefits of constraining inhibitors into the extended bioactive conformation known as a β-strand. Ring closing metathesis is utilised in the synthesis of the macrocyclic aldehyde 4.4, macrocyclic semicarbazone 4.15, the macrocyclic cyanohydrin 4.16, the macrocyclic α-ketotetrazole 4.18 and the macrocyclic azide 4.19. Chapter Five introduces enzyme inhibition studies. The BODIPY-casein fluorogenic assay used for establishing inhibitor potency against m-calpain and μ-calpain is validated. Assay protocols are also established and validated for cathepsin B, papain, pepsin and α- chymotrypsin. A discussion of the effect of solvent on enzyme activity is also included as part of this study. Chapter Six presents the assay results for all the inhibitors synthesised throughout this thesis and an extensive structure-activity relationship study between inhibitors is included. The alcohols 2.26 and 2.30 are unprecedented examples of non-covalent, potent, cathepsin B inhibitors (IC₅₀ = 0.075 μM selectivity 80-fold and 1.1 μM, selectivity 18-fold). The macrocyclic semicarbazone 4.15 is an unprecedented example of a potent macrocyclic cysteine protease inhibitor (m-calpain: IC₅₀ = 0.16 μM, selectivity 8-fold). The cyanohydrin 2.51 contains an unprecedented cysteine protease warhead and is a potent and selective inhibitor of papain (IC₅₀ = 0.030 μM, selectivity 3-fold). The O-protected cyanohydrin 2.61 is a potent and selective inhibitor of pepsin (IC₅₀ = 1.6 μM, selectivity 1.5-fold). The top ten warheads for potent, selective cathepsin B inhibition are: carboxylic acid, methyl ester, diazoketone, esterified cyanohydrin, α-bromomethyl ketone, α,β- unsaturated aldehyde, vinyl sulfones, α-bromomethyl-C₃-S,R-alcohol, alcohol and α,β- unsaturated ethyl ester. The selectivity of these warheads was between 5- and 130-fold for cathepsin B. The best inhibitors for cathepsin B were the α-bromomethyl ketone 3.26 (IC₅₀ = 0.075 μM, selectivity 16-fold), the α,β-unsaturated aldehyde 3.18 (IC₅₀ = 0.13 μM, selectivity 13-fold) and the esterified cyanohydrin 3.59 (IC₅₀ = 0.35 μM, selectivity 22- fold). Chapter Seven outlines the experimental details and synthesis of the compounds prepared in this thesis.

Gli stili APA, Harvard, Vancouver, ISO e altri

Bridges, Sylvia Shadinger. "Design, synthesis, and evaluation of cysteine protease inhibitors". Diss., Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/29738.

Testo completo

Abstract (sommario):

Proteases are enzymes that cleave protein amide bonds. Proteases are involved in a myriad of biological processes and are considered good targets for drug design. The proteases described herein are cysteine proteases, which utilize a cysteine residue thiol to attack the amide carbonyl, leading to amide bond cleavage. Irreversible inhibitors of cysteine proteases react with the active site cysteine, forming a covalent bond and rendering the enzyme inactive. The first project involved the design and synthesis of aza-peptide epoxide inhibitors for calpain, a clan CA, ubiquitous, calcium-activated human enzyme involved in neurodegeneration. These inhibitors proved to be poor inactivators of calpain, demonstrating that the aza-peptide epoxide is a warhead specific to clan CD cysteine proteases (caspases, gingipains). Subsequently, a known epoxide inhibitor of calpain was optimized to create a more potent inhibitor. Several of these inhibitors were more potent than the parent, and all were demonstrated to inhibit calpain in a breast cancer cell line which was treated with paclitaxel to spike calpain activity. The second project involved the design and solid phase synthesis of aza-peptide Michael acceptor caspases inhibitors. The two goals of this project were to develop a solid phase method for synthesis of inhibitors that are tedious to synthesize in solution phase, and to use a variety of amino acid residues to determine the optimal interactions in the P3? position for various caspases. The synthesis was successful, and the optimal P3? residues were determined. The third project involved the kinetic evaluation of aza-peptide epoxide and Michael acceptor inhibitor designed for the gingipains. Gingipains K and R are virulence factors in the pathology of Porphyromonas gingivalis involved in gingivitis and periodontal disease. These inhibitors proved to be extremely potent inactivators of gingipains, with some of the highest rates of inhibition measured in the Powers laboratory. Gingipain K preferred larger, aromatic moieties in the P1? position, while gingipain R preferred the Michael acceptor inhibitors, with the P1? substituent having less of an impact on potency.

Gli stili APA, Harvard, Vancouver, ISO e altri

Più fonti

Libri sul tema "Cysteine protease inhibitor"

Cystatins: Protease inhibitors, biomarkers, and immunomodulators. New York: Nova Science, 2011.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Estrada, Sergio. Cystatin A, a mammalian cysteine proteinase inhibitor: Mechanism of inhibition of target proteinases by recombinant cystatin A variants. Uppsala: Sveriges Lantbruksuniversitet, 1998.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Turk, Boris. Papain-like cysteine proteinases: Regulation by proteinase inhibitors and pH. Uppsala: SverigesLantbruksuniversitet, 1996.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Philippe, Taupin, a cura di. The cystatin superfamily of proteinase inhibitors. New York: Nova Science Publishers, 2007.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Turk, Vito. Cysteine Proteinases and their Inhibitors: Proceedings of the International Symposium Portoroz, Yugoslavia, September 15-18 1985. De Gruyter, Inc., 2019.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Vito, Turk, e International Symposium on Cysteine Proteinases and Their Inhibitors (1st : 1985 : Portorož, Slovenia), a cura di. Cysteine proteinases and their inhibitors: Proceedings of the international symposium, Portorož, Yugoslavia, September 15-18, 1985. Berlin: De Gruyter, 1986.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Akpinar, Ozlem. Characterization of recombinant proteinase inhibitors in surimi application. 1998.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

(Editor), Michael F. Shaughnessy, Marcel V. e. Vennemann (Editor) e Cynthia Kleyn Kennedy (Editor), a cura di. Meta-Cognition: A Recent Review of Research, Theory, and Perspectives. Nova Science Publishers Inc, 2008.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

F, Shaughnessy Michael, Veenman Marcel e Kennedy Cynthia Kleyn, a cura di. Meta-cognition: A recent review of research, theory, and perspectives. New York: Nova Science Publishers, Inc., 2007.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

F, Shaughnessy Michael, Veenman Marcel e Kennedy Cynthia Kleyn, a cura di. Meta-cognition: A recent review of research, theory, and perspectives. New York: Nova Science Publishers, Inc., 2008.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Capitoli di libri sul tema "Cysteine protease inhibitor"

Nishida, Y., H. Tsushima, N. Toki, H. Sumi e H. Mihara. "Thiol protease inhibitor released from human malignant melanoma". In Cysteine Proteinases and their Inhibitors, a cura di Vito Turk, 751–60. Berlin, Boston: De Gruyter, 1986. http://dx.doi.org/10.1515/9783110846836-069.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Arthur, Gavin D., e Angelo N. Belcastro. "Cardiac Adaptations to Swim Exercise with Administration of a Cysteine Protease Inhibitor". In Progress in Experimental Cardiology, 519–33. Boston, MA: Springer US, 2003. http://dx.doi.org/10.1007/978-1-4615-0455-9_38.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Levine, A., B. Belinghi, M. Solomon, E. Menachem e M. Delledonne. "Regulation of Programmed Cell Death in Cultured Soybean Cells by a Cysteine Protease Inhibitor". In Plant Biotechnology and In Vitro Biology in the 21st Century, 421–24. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-011-4661-6_94.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Zhou, Jinlin, e Kozo Fujisaki. "A cysteine protease inhibitor (cystatin) from the tick Haemaphysalis longicornis is involved in tick innate immunity". In Trends in Acarology, 227–31. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-9837-5_37.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Lonsdale-Eccles, J. D., e D. J. Grab. "Proteases in African trypanosomes". In Cysteine Proteinases and their Inhibitors, a cura di Vito Turk, 189–98. Berlin, Boston: De Gruyter, 1986. http://dx.doi.org/10.1515/9783110846836-022.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Chatterjee, R., M. Lones e G. Kalnitsky. "Histone degradation by lysosomal proteases". In Cysteine Proteinases and their Inhibitors, a cura di Vito Turk, 97–110. Berlin, Boston: De Gruyter, 1986. http://dx.doi.org/10.1515/9783110846836-015.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Korant, B., T. Towatari, L. Ivanoff, C. Kettner, A. Cordova e S. Petteway. "Viruses as vectors for cysteine proteases". In Cysteine Proteinases and their Inhibitors, a cura di Vito Turk, 293–306. Berlin, Boston: De Gruyter, 1986. http://dx.doi.org/10.1515/9783110846836-032.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Nandy, Suman K. "A Brief Account of Structure-Function Relationship of the Traditional Cysteine Protease Inhibitor - Cystatin with a Special Focus on Human Family 1 and 2 Cystatins". In Proteases in Physiology and Pathology, 579–605. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-2513-6_27.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Kawashima, G., M. Inomata e K. Imahori. "Control mechanism of calcium-activated neutral protease (CANP) activity". In Cysteine Proteinases and their Inhibitors, a cura di Vito Turk, 359–68. Berlin, Boston: De Gruyter, 1986. http://dx.doi.org/10.1515/9783110846836-036.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Ghosh, Arun K., e Sandra Gemma. "Design of Cysteine Protease Inhibitors". In Structure-Based Design of Drugs and Other Bioactive Molecules, 131–42. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527665211.ch5.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Atti di convegni sul tema "Cysteine protease inhibitor"

Suzuki, Koji, Yoshihiro Deyashiki, Junji Nishioka, Kazunori Toma e Shuji Yamamoto. "THE INHIBITOR OF ACTIVATED PROTEIN C: STRUCTURE AND FUNCTION". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642963.

Testo completo

Abstract (sommario):

In the final step of protein C pathway, activated protein C (APC) is neutralized with a plasma inhibitor, termed protein C inhibitor (PCI). PCI was first described by Marlar and Griffin (1980) and then isolated from human plasma as a homogeneous form and characterized by the authors (1983). PCI is a single chain glycoprotein with M 57,000 and a plasma concentration of 5 ug/ml. Analysis of a cDNA nucleotide sequence has clarified that a precursor of human PCI consists of a mature protein of 387 amino acid residues (M 43,759) and a signal peptide of 19 amino acid residues. Only one cysteine residue is present in the entire protein as in α1antitrypsin (α1AT) and α1antichymotrypsin (α1ACT). Three Asn-X-Ser/Thr sequences and two Ser/Thr-X-X-Pro sequences are present as potential attachment sites of carbohydrate chains. Based on the amino acid sequence of the carboxyl-terminal peptide released from the inhibitor by APC digestion, the reactive site peptide bond of PCI was found to be Arg(354)-Ser(355). It is similar to the reactive sites of the other serine protease inhibitors which are located to their carboxyl-terminal Arg(393)-Ser (394), Met(358)-Ser(359) and Leu(358)-Ser(359) in antithrombin III, α1AT and α1ACT, respectively. The alignment of the amino acid sequence of PCI with heparin cofactor II, α1plasmin inhibitor, ovalbumin, angiotensinogen and the above noted plasma inhibitors showed that PCI is a member of serine protease inhibitor superfamily. PCI inhibits APC noncompetitively in a 1:1 stoichiometry and forms a covalent acyl-bond with a Ser residue in the active center of APC. The half life of APC in plasma approximately 30 min, which is rather slow compared with the other protease inhibitors. However, optimal concentrations of heparin, dextran sulfate and its derivatives potentiate the rate of inhibition 30-60 fold. PCI has Ki of 10-8m for APC, and can inhibit thrombin, Factor Xa, urokinase and tissue plasminogen activator as well in the presence of heparin or dextran sulfate, though the Ki for these enzymes is slightly higher. During the complex formation with APC, PCI is cleaved by the complexed APC to form a modified form with M 54,000. PCI is synthesized in several hepatoma cell lines and decreased in plasma of patients with liver cirrhosis. It is also decreased in patients with DIC or those during cardiopulmonary bypass in parallel with the decrease in protein C, suggesting that PCI participates in regulation of the protein C pathway in intravascular coagulation. Recently, we have obtained the recombinant PCI from COS-1 cells which were transfected with expression vector pSV2 containing the cDNA of PCI. The recombinant PCI had the same Mr and specific activity as the protein purified from plasma. It also had an affinity for heparin and dextran sulfate. Moreover, we have predicted a three dimentional structure of the proteolytically modified PCI with computer graphics based on its amino acid sequence homology with the modified α1AT whose structure had been elucidated with X-ray crystallography. All potential carbohydrate attachment sites were estimated to exist on the surface of the protein. Succesively we have constructed the interaction model between the intact PCI predicted from the modified form and the active center of APC which was simulated from that of trypsin. From the model, it was observed that the amino-group of Arg (354, PI site) of PCI could strongly interact with the carboxy1-group of Asp (88, SI site) of the heavy chain of APC at the base of the active center pocket of the enzyme.

Gli stili APA, Harvard, Vancouver, ISO e altri

Roncaglioni, M. C., A. Falanga, A. P. Bolognese Dalessandro, B. Casali e M. B. Donti. "ENZYMATIC AND IMMUNOLOGIC CHARACTERIZATION OF A CYSTEINE PROTEINASE PROCOAGULANT IN SEVERAL MURINE METASTASIZING TUMO". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643663.

Testo completo

Abstract (sommario):

Involvement of the hemostatic systemin tumor metastasis growth has been repeatedly suggested and several tumor-associated procoagulants have been described. We have studied here the procoagulant activity (PCA) of tissue extracts from 4 murine metastasizing tumors: Lewis Lung Carcinoma (3LL), B16 melanoma (B16), JW sarcoma (JWS) and the M4 variant of the mFS6 fibrosarcoma (M4). The experiments were designed to identify cancer procoagulant (CP) a FVII independent FX activating cysteine proteinase or tissue factor (TF) in these tumors. Tissue extracts from 3LL, B16 and JWS initiated coagulation both in the presence and absence of FVII (FVII independent activity ranging from 70% to 86% of the total activity). The PCA of the same tumors was significantly decreased (p < 0.01) by cysteine proteinase inhibitors (1 mM iodoacetamide (IA) and 0.1 mM HgCl2 ) and the inhibitionby HgCl2 was reversed by -SH group activators (di-thiatreital, KCN, IiDTA). In addition these samples were able of directly activating pure bovineFX in a two stage clotting assay. The PCA of M4 extract was dependent on FVII,was not significantly affected by IA and HgCl2 and was inhibited by concanavalin A, a known TF inhibitor. An Ouchterlony double immunodiffusion study showed immunological cross-reactivity of 3LL, B16 and JWS to a polyclonal antibody to purified CP (from rabbit V2 carcinoma; obtained from S.G. Gordon, Denver, USA). No cross-reactivity was present between this antibody and M4. This study shows that the PCA of M4 is TF, whereas the procoagulant(s) of 3LL, B16 and JWS are enzymatically and immunologically indistinguishable from CP.

Gli stili APA, Harvard, Vancouver, ISO e altri

Loskutoff, D. J., J. Mimuro e C. Hekman. "PLASMINOGEN ACTIVATOR INHIBITOR". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644763.

Testo completo

Abstract (sommario):

Plasminogen activation provides an important source of localized proteolytic activity not only during fibrinolysis, but also during ovulation, cell migration, epithelial cell differentiation, tumor invasion and a variety of other physiological processes. Precise regulation of plasminogen activator (PA) activity thus constitutes a critical feature of many biological processes. This control is achieved in large part through the action of specific PA inhibitors (PAIs). Although 4 distinct PAIs have been detected,1the endothelial cellTderived inhibitor (PAI-1) is the only one that efficiently inhibits both urokinase (Kd=2.3×10−13M; Kassoc =1.6×108 M−1s−1) and single-chaintissue-type PA (tPA; Kd=1.3×lO−15 M Kd=3.9×lO7M−1s−1). It also inhibits trypsin (Kassoc=6.8×106M−1 s−1 ) ancl Plasmin (Kassoc=7.6×l05 M−1 s5 Analysis of the effect of PAI-1 on the rate of plasminogen activation revealed a competitive type of inhibition when urokinase was employed but a linear mixed type of inhibition when single chain tPA was employed. These results suggest that the interaction of PAI-1 with tPA, in contrast to its interaction with urokinase, may involve 2 sites on the tPA molecule.PAI-1 has been purified from medium conditioned by cultured bovine aortic endothelial cells and partially characterized. It is a major biosynthetic product of these cells, accounting for as much as 12% of the total protein released by the cells in 24 h. It has an M of 50,000, an isoelectric point of 4.5-5.0, and is immunologically and biochemically related to the rapidly acting inhibitor present in human platelets and in the plasma of some patients at risk to develop thrombotic problems. Although it is relatively stable to conditions which inactivate most protease inhibitors (acid pH, SDS), it is extremely sensitive to oxidants. The molecular cloning of the PAI-1 gene revealed that the mature human protein is 379 amino acids long, contains an NH2-terminal valine, lacks cysteines and has a methionine at the Pi position of it's reactive center. The conversion of this methionine to methionine sulfoxide may be responsible for the rapid inactivation of PAI-1 by oxidants. Human PAI-1 has extensive (30%) homology with α1-antitrypsin and antithrombin III and is thus a member of the serine proteinase inhibitor (serpin) family; a group of related molecules that control the major protease cascades of the blood. The PAI-1 gene is approximately 12.2 kilobase pairs in length and is organized into nine exons and eight introns.The production of PAI-1 by endothelial cells is stimulated by endotoxin, interleukin-1, tumor necrosis factor, and transforming growth factor β(TGFβ). The cells are extremely sensitive to TGFβwith maximal effects (100-fold stimulation) observed with 1-2 ng/ml. These changes were relatively specific for PAI-1, and could be detected at both the protein and the RNA level. Interestingly, TGFgalso stimulated the amount of PAI-1 present in the extracellular matrix (ECM) of BAEs. PAI-1 was one of the primary ECM components of these cells, constituting 10-20% of the ECM proteins detected after SDS-PAGE.One of the most unusual properties of PAI-1 is that it exists in blood and in various cellular samples in both an active and an inactive (latent) form, the ratio depending on the source. The latent form can be converted into the active one by treatment with denaturants like SDS or guanidine-HCl. Although the majority of the cell-associated PAI-1 is active, it rapidly decays (t1/2=3 h) into the latent form once it is released from the cells. In contrast, the half-life of ECM associated PAI-1 was greater than 24 h. These data suggest that PAI-1 is produced by BAEs in an active form, and is then either released into the medium where it is rapidly inactivated, or released into the subendothelium where it binds to ECM. The specific binding of PAI-1 to ECM protects it from this inactivation.

Gli stili APA, Harvard, Vancouver, ISO e altri

Grignani, G., L. Pacchiarini, M. Zucchella, L. Dezza e S. C. Rizzo. "PLATELET ACTIVATION BY HUMAN CANCER CELLS GROWN “IN VITRO” OR DISSOCIATED FROM TUMOUR TISSUES". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643200.

Testo completo

Abstract (sommario):

The mechanisms of platelet activation by human tumour cells grown “in vitro” or freshly dissociated from tumour tissues have been investigated.MoCCL human T-lymphoblastic cells cultured “in vitro” induced platelet aggregation through the production of ADP, as evidenced by inhibition of the effect by apyrase. The maximum of ADP production by tumour cells was reached after 1 hour and was 225 p moles/106 cells.On the contrary, platelet aggregation induced by 5637 human bladder carcinoma cells was not inhibited by apyrase, but was abolished by hirudin, indicating the important role of thrombin in this effect.Tumour cells dissociated from 3 breast carcinomas showed a very high platelet aggregating activity, which was not inhibited by hirudin or apyrase, but was abolished by iodoacetic acid, suggesting a role for a cystein-protease in platelet activation.These results confirm that platelets can be activated by tumour cells through different mechanisms; they also suggest that the methods employed to obtain the tumour cells can influence the results, probably because of the different cell populations which are present in the dissociated tumour tissues.Informations obtained with freshly dissociated cells are interesting, because this method has been used seldom so far and because it provides a more physiological approach to the study of the interactions of tumours and platelets.

Gli stili APA, Harvard, Vancouver, ISO e altri

Kossack, R., S. Breinlinger, T. Nguyen, T. Schirmeister, H. Enke e T. Niedermeyer. "The putative PAINs nostotrebin 6 and derivatives from Nostoc sp. inhibit the trypanosomal cysteine protease rhodesain". In GA 2017 – Book of Abstracts. Georg Thieme Verlag KG, 2017. http://dx.doi.org/10.1055/s-0037-1608156.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Gordon, Stuart, Bonnie Sloane, Phil Cavanugh, Barbara Cross, Kenneth Honn e Mohanathasan Chelladurai. "PURIFICATION AND CHARACTERIZATION OF TWO PROCOAGULANTS FROM WALKER 256 CARCINOSARCOMA TUMORS",. In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643666.

Testo completo

Abstract (sommario):

Activation of the coagulation system bytumor cells may play an important role in tumor growth and metastases. Becauseprocoagulant activities have been identified in different tumor cells by different investigators, effective comparison of these activities has been difficult. Therefore, we purified and characterized two different procoagulant proteins from the same Walker 256 tumors. The first procoagulant activity/platelet aggregating activity (PCA/PAA) was purified from a 1% CHAPS detergent extract oftumor homogenate followed by (NH4)2SO4 fractionation, anion exchange and hydrophobic chromatography. The protein had a molecular weight of 58,000, required phospholipid and an intact coagulation pathway from factor X through fibrinogen for activity, but did not require factors VII or IX forits procoagulant activity. The procoagulant activity was not inhibited by 5mMphenyl-methyl sulfonyl fluoride, iodoacetamide or phenanthroline; there was noevidence of proteinase activity. The PAA was due to thrombin generation during coagulation. The second procoagulant,cancer procoagulant (CP), was extracted from tumors in barbital buffer (pH 7.4) without detergent, purified by immunoaffinity (using a polyclonal goat antibody to CP from V2 carcinoma) and mercurial-benzoate affinity chromatography. CP had a molecular weight of 68,000, an isoelectric point of 4.8 and initiated coagulation by directly activating factor X in the coagulation system. CP was inhibited by Hg++ and iodoacetamide, cysteine proteinase inhibitors. The purified CP formed an immunodiffusion precipitin band against the polyclonal anti-CP goat antibody. Thus, thepurified CP had the same physicochemical, enzymatic and immunologic propertiesas CP from rabbit V2 carcinoma. Neither procoagulant had the properties of tissue factor. These results suggest that there aretwo distinct procoagulant activities inWalker 256 and that both may contributeto the coagulation abnormalities that are associated with tumor growthand metastases.

Gli stili APA, Harvard, Vancouver, ISO e altri

Ishiguro, H., S. Higashiyama, C. Namikawa, I. Ohkubo e M. Sasaki. "MAPPING OF FUNCTIONAL DOMAINS OF HUMAN HIGH MOLECULAR WEIGHT (HMW) AND LOW MOLECULAR WEIGHT (LMW) KININOGENS BY USING MURINE MONOCLONAL ANTIBODIES (MAbs)". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642849.

Testo completo

Abstract (sommario):

It has been widely known that HMW and LMW kininogens are the large potential sources of kinin in human blood, and that HMW kininogen also functions as a cofactor in the contact activation of blood coagulation. Recently, it has been demonstrated that the heavy chains of kininogens strongly inhibited a number of cysteine proteinases such as calpains, cathepsins, papain and ficin. We made an attempt at mapping of functional domains on the molecules of both kininogens by using MAbs.Thirty four MAbs raised against human HMW and LMW kininogens were screened by ELISA. By using HMW kininogen, kinin-free HMW kininogen, kinin and fragment 1.2 (fr 1.2)-free HMW kininogen, LMW kininogen, kinin-free LMW kininogen, heavy chain of LMW kininogen and light chains of both kininogens, the MAbs were characterized and.classified into four groups; [1] 20 MAbs reacted with heavy chain, a common region of HMW and LMW kininogens. These MAbs possessed the specificity for domain 1 (2 MAbs), domain 2 (2 MAbs), domain 3 (7 MAbs), and both domains 2 and 3 (7 MAbs) of the heavy chain; [2] 7 MAbs recognized the fr 1.2, a unique histidine-rich region; [3] 5 MAbs reacted with the light chain of HMW kininogen; [4] 2 MAbs recognized the light chain of LMW kininogen.Two MAbs, designated HKG H7 and H12, effectively inhibited the cysteine proteinase inhibitor activity of HMW and LMW kininogens and the others did not affect it. Further, the MAbs, which recognized the fr 1.2 or light chain of HMW kininogen, suppressed the clotting activity. Especially, 2 MAbs, named HKG L2 and L5, effectively suppressed the clotting activity of HMW kininogen. The former, which neutralized about 70% of the clotting activity, reacted specifically with fr 1.2 region of HMW kininogen, and the latter, which neutralized more than 90% of it, recognized the light chain of HMW kininogen. In the results of competition ELISA, fr 1.2 specific MAbs could be classified into 5 kinds of MAbs for recognition sites, and the light chain (HMW kininogen)-specific MAbs also could be classified into 3 kinds of MAbs. Further, 2 light chain (LMW kininogen)-specific MAbs were thought to recognize an identical antigenic site.

Gli stili APA, Harvard, Vancouver, ISO e altri

Falang, A., G. M. Alessio, M. Donati e T. A. Barbui. "DISSEMINATED INTRAVASCULAR COAGULATION (DIC) AND ACUTE LEUKEMIA:IDENTIFICATION OF A NEW CELLULAR PROCOAGULANT". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643661.

Testo completo

Abstract (sommario):

There is an enhanced incidence (>50%) of severe coagulopathy in association with several types of acute leukemias. Cell associated procoagulants are considered important in this context. So far only a Tissue Factor (TF)-type procoagulant has been described in leukemic cells. We have set up here the experimentalconditions to identify other possible cellular procoagulants in leukemia. We have tested blast cell extracts from 21 patients with 5 different cytological subtypes (from Ml to M5 of acute non lymphoid leukemia (ANLL), according to theFAB classification, in order to assay whether they express "cancer procoagulant" (CP), a F VH-independent FX activating cysteine proteinase (Falanga … Gordon, 1985; Donati, et al. 1986). All the samples shortened the recalcification time of normal human plasma, the effect being significantly greater (p<0.001) in the M3 group. The activity was 20% to 100% independent from the presence of FVII and was susceptible to 2 cysteine proteinase inhibitors (Iodoacetamide, 2 mM, and HgCl2 ,0.1 mM) in all of the extracts but the M5 type. In addition, M2 and M3 samples directly activated pure FX in a two stage clotting assay. Control cell extracts from 10 healthy donors did not show any procoagulant activity, under the same conditions. This study provides evidence for a new procoagulant expressed by cells of ANLL; the peculiar characteristics of this procoagulant (i.e. its confinement to the malignant phenotype, its shedding into the plasma, its possible modulation by vitamin K antagonists) make this observation of potential interest in the development of new diagnostic and therapeutic tools in ANLL.

Gli stili APA, Harvard, Vancouver, ISO e altri

Higashiyama, S., I. Ohkubo, H. Ishiguro e M. Sasaki. "A NEW FUNCTION OF HUMAN KININOGENS: THE AMINO-TERMINAL REGION OF DOMAIN 1 INVOLVES AN EF HAND-LIKE STRACTURE FOR METAL BINDING". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642851.

Testo completo

Abstract (sommario):

Two types of kininogens in mammalian plasma, high molecular weight (HMW) and low molecular weight (LMW) kininogens, are the precursors of kinin. Especially, HMW kininogen circulates in the plasma as a complex with prekallikrein and factor XI, and functions as a cofactor in the initial phase reactions of intrinsic blood coagulation cascade. Recently, it has been found that the kininogens have inhibitory activity toward cysteine proteinases. The heavy chain portion, which is identical for HMW and LMW kininogens, is composed of three domains, domain 1, 2 and 3. Each the domain 2 and 3 has a reactive site as a cysteine proteinase inhibitor. However, physiological function of domain 1 remains still unknown. By using the antibody recognizing the interaction between HMW kininogen and Ca2+ (anti-HMW kininogen-Ca2+ antibody) as a probe, we newly found the Ca2+ binding site in the domain 1.Anti-HMW kininogen-Ca2+ antibody was isolated from anti-HMW kininogen antiserum as an antibody which bound to a HMW kininogen-Sepharose column equilibrated with 40 mM Tris-HCl buffer, pH 7.5, containing 1.0 M NaCl and 1 mM CaCl2, and was eluted with 3 mM EDTA. Resulting from the characterization by ELISA, this antibody specifically recognized the CB-1 region (CNBr-cleavage fragment 1: 1-160 amino acid sequence) of the heavy chain of kininogen molecules in the presence of Ca2+ or Mg2+. Furthermore, circular dichroism (CD) experiments showed that the conformational changes of HMW kininogen and heavy chain were induced by the addition of metal ions such as Ca2+ or Mg2+, and that this change was due to the conformational change of the CB-1 region. The dissociation constant (Kd) for heavy chain measured by Ca2+ titration analysis by CD at 214 nm was found to be 0.33 ± 0.09 mM. The number of Ca2+ binding sites of heavy chain calculated from Hill plot was 1.15 ± 0.04. The EF handlike structure found in the amino-terminal portion of the heavy chain of kininogen molecules strongly supported the above data. This indicates a possibility that kininogens play an important role as a Ca2+ binding protein.

Gli stili APA, Harvard, Vancouver, ISO e altri

Rapporti di organizzazioni sul tema "Cysteine protease inhibitor"

Sanders, Tanya C. A New Class of Serine and Cysteine Protease Inhibitor with Chemotherapeutic Potential. Fort Belvoir, VA: Defense Technical Information Center, giugno 1999. http://dx.doi.org/10.21236/ada370850.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Sanders, Tanya C. A New Class of Serine and Cysteine Protease Inhibitor with Chemotherapeutic Potential. Fort Belvoir, VA: Defense Technical Information Center, luglio 1998. http://dx.doi.org/10.21236/ada353868.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Seto, Christopher. Anticancer Agents Based on a New Class of Transition-State Analog Inhibitors for Serine and Cysteine Proteases. Fort Belvoir, VA: Defense Technical Information Center, agosto 2000. http://dx.doi.org/10.21236/ada383963.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Seto, Christopher T. Anticancer Agents Based on a New Class of Transition- State Analog Inhibitors for Serine and Cysteine Proteases. Fort Belvoir, VA: Defense Technical Information Center, agosto 1999. http://dx.doi.org/10.21236/ada377205.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Offriamo sconti su tutti i piani premium per gli autori le cui opere sono incluse in raccolte letterarie tematiche. Contattaci per ottenere un codice promozionale unico!