Search results for "carboxypeptidase"
showing 10 items of 29 documents
Reverse screening on indicaxanthin from Opuntia ficus-indica as natural chemoactive and chemopreventive agent
2018
Indicaxanthin is a bioactive and bioavailable betalain pigment extracted from Opuntia ficus indica fruits. Indicaxanthin has pharmacokinetic proprieties, rarely found in other phytochemicals, and it has been demonstrated that it provides a broad-spectrum of pharmaceutical activity, exerting anti-proliferative, anti-inflammatory, and neuromodulator effects. The discovery of the Indicaxanthin physiological targets plays an important role in understanding the biochemical mechanism. In this study, combined reverse pharmacophore mapping, reverse docking, and text-based database search identified Inositol Trisphosphate 3-Kinase (ITP3K-A), Glutamate carboxypeptidase II (GCPII), Leukotriene-A4 hydr…
Demonstration of High-Affinity Binding Sites for C3a Anaphylatoxin on Guinea-Pig Platelets
1978
3H-serotonin release from guinea-pig platelets was demonstrated to be the consequence of C3a binding to these cells. A Scatchard analysis of dose-response data of the 125I-C3a binding pattern to guinea-pig platelets pointed to the existence of binding sites with high and low affinity for the C3a molecule (HA and LA receptors). HA receptors are specific for C3a with intact C-terminal arginine. whereas C3adesarg only interacts with LA receptors. The release of serotonin may be induced by a combined reaction of C3a with HA receptors and LA receptors on the platelet membrane.
Cre-mediated cell ablation contests mast cell contribution in models of antibody- and T cell-mediated autoimmunity.
2011
SummaryImmunological functions of mast cells remain poorly understood. Studies in Kit mutant mice suggest key roles for mast cells in certain antibody- and T cell-mediated autoimmune diseases. However, Kit mutations affect multiple cell types of both immune and nonimmune origin. Here, we show that targeted insertion of Cre-recombinase into the mast cell carboxypeptidase A3 locus deleted mast cells in connective and mucosal tissues by a genotoxic Trp53-dependent mechanism. Cre-mediated mast cell eradication (Cre-Master) mice had, with the exception of a lack of mast cells and reduced basophils, a normal immune system. Cre-Master mice were refractory to IgE-mediated anaphylaxis, and this defe…
d-Alanyl-d-Alanine Carboxypeptidase in the Bacterial Form and L-Form of Proteus mirabilis
1975
Membranes of the bacterial form and the stable and unstable L-forms of Proteus mirabilis contain LD and DD-carboxypeptidase. The DD-carboxypeptidase is inhibited non-competitively by penicillin G. The enzyme of the bacterial form is highly penicillin-sensitive (Ki - 4 X 10(-9) M penicillin G). Inhibition is only partly reversible by treatment with penicillinase or by dialysis against buffer. In contrast, the DD-carboxypeptidase of the unstable L-form, grown in the presence of penicillin, is 175-fold less penicillin-sensitive (Ki = 7 X 10(7) M penicillin G). Inhibition is completely reversed by penicillinase or dialysis. After inhibition by penicillin and subsequent reactivation the penicill…
Hybrid Chelator-Based PSMA Radiopharmaceuticals: Translational Approach
2021
(1) Background: Prostate-specific membrane antigen (PSMA) has been extensively studied in the last decade. It became a promising biological target in the diagnosis and therapy of PSMA-expressing cancer diseases. Although there are several radiolabeled PSMA inhibitors available, the search for new compounds with improved pharmacokinetic properties and simplified synthesis is still ongoing. In this study, we developed PSMA ligands with two different hybrid chelators and a modified linker. Both compounds have displayed a promising pharmacokinetic profile. (2) Methods: DATA5m.SA.KuE and AAZTA5.SA.KuE were synthesized. DATA5m.SA.KuE was labeled with gallium-68 and radiochemical yields of various…
Peptidases in Germinating Barley Grain: Properties, Localization and Possible Functions
2008
Barley grain contains about 10% insoluble reserve proteins. When the grain germinates the reserve proteins are hydrolysed to amino acids and transported to the growing tissues of the seedling. In the resting grain most of the reserve proteins are 'packed' into the non-living storage tissue, the starchy endosperm. During germination the internal pH of the starchy endosperm is about 5, and it contains high activities of proteinases (secreted by the living aleurone cells) and carboxypeptidases, all with pH optima between 4 and 6. As a whole the starchy endosperm of a germinating grain resembles a giant secondary lysosome. Adjacent to the starchy endosperm is a specialized absorptive and proces…
Mobilization of proline in the starchy endosperm of germinating barley grain.
1979
In germinating grains of barley, Hordeum vulgare L. cv. Himalaya, free proline accumulated in the starchy endosperm during the period of rapid mobilization of reserve proteins. When starchy endosperms were separated from germinating grains and homogenized in a dilute buffer of pH 5 (the pH of the starchy endosperm), the liberation of proline continued in these suspensions. The process was completely inhibited by diisopropylfluorophosphate, indicating that it was totally dependent on serine carboxy-peptidases. The carboxypeptidases present in the starchy endosperms of germinating grains were fractionated by chromatography on DEAE-cellulose. Four peaks were obtained, all with different activi…
Properties and amino acid composition of pure epoxide hydratase
1975
1. Introduction Rat liver epoxide hydratase [EC 4.2.1.631 which catalyses the conversion of epoxides to trurans-dihydro- diols has been purified to apparent homogeneity as determined by three independent criteria [l] . The preparation obtained was capable of catalysing the hydration of both styrene oxide and the 4,5- (K- region)epoxide of benzo(a)pyrene [ 11. Epoxides of polycyclic hydrocarbons have been implicated as the agents responsible for the cytotoxic and carcinogenic properties of such compounds (for reviews see [2-41). A detailed knowledge of the properties of epoxide hydratase may, therefore, contribute towards an understanding of the mechanisms of cytotoxicity and carcinogenesis.…
(R)-NODAGA-PSMA: A Versatile Precursor for Radiometal Labeling and Nuclear Imaging of PSMA-Positive Tumors
2015
Purpose The present study aims at developing and evaluating an urea-based prostate specific membrane antigen (PSMA) inhibitor suitable for labeling with 111In for SPECT and intraoperative applications as well as 68Ga and 64Cu for PET imaging. Methods The PSMA-based inhibitor-lysine-urea-glutamate-coupled to the spacer Phe-Phe-D-Lys(suberoyl) and functionalized with the enantiomerically pure prochelator (R)-1-(1-carboxy-3-carbotertbutoxypropyl)-4,7-carbotartbutoxymethyl)-1,4,7-triazacyclononane ((R)-NODAGA(tBu)3), to obtain (R)-NODAGA-Phe-Phe-D-Lys(suberoyl)-Lys-urea-Glu (CC34). CC34 was labeled with 111In, 68Ga and 64Cu. The radioconjugates were further evaluated in vitro and in vivo in LNC…
Activated thrombin activatable fibrinolysis inhibitor levels are associated with the risk of cardiovascular death in patients with coronary artery di…
2008
Summary. Background: Thrombin activatable fibrinolysis inhibitor (TAFI) attenuates fibrinolysis. Results on the association between TAFI levels and the risk of coronary artery disease (CAD) are inconsistent. Objectives: We investigated the association between TAFI levels and the risk of cardiovascular events in CAD. Patients/Methods: 1668 individuals with angiographically proven CAD at baseline were followed for a median of 2.3 years, as part of the prospective AtheroGene cohort. Fifty-six deaths from cardiovascular (CV) causes and 35 non-fatal CV events were observed. Results: At baseline, three TAFI measurements were available: one evaluating the total amount of TAFI (t-TAFI), one measuri…