Search results for "Peptide Hydrolase"

Distribution of protease activity in the blastula and early gastrula ofDiscoglossus pictus

1957

E stata determinata l'attivita proteasica nelle differenti regioni della blastula e della gastrula diDiscoglossus pictus. Nella blastula non esiste una differenza di attivita fra meta animale e vegetativa, quando si prenda come riferimento l'azoto citoplasmatico. Nella giovane gastrula il territorio presuntivo della corda e del sistema nervoso mostra una attivita piu elevata della epidermide presuntiva.

Activation of the first component of complement, C1: comparison of the effect of sixteen different enzymes on serum C1.

1983

In this study, the effect of sixteen different enzymes on serum C1 and its subcomponents was investigated. The sixteen enzymes could be divided into three groups. First, enzymes which activate native C1: trypsin (optimal concentration 2.4 x 10(-4) mM); alpha-chymotrypsin (2.3 x 10(3) mM); thrombin (1.0 x 10(-5) mM); plasmin (1.9 x 10(-5) mM); elastase (5.8 x 10(-5) mM); pronase (3.0 x 10(-6) mM). All these enzymes are serine esterase and activate native serum C1 bound to EAC4 at the given concentration within 10 min at 30 degrees C. Furthermore, native C1 inhibited by a pentosanpolysulfoester, Sp54, is unable to undergo the internal activation but can be externally activated by the serine e…

A48 COLITIS FAVORS THE EXPANSION OF BACTERIA THAT ACTIVATE PAR2 AMPLIFYING INFLAMMATORY RESPONSE

2020

Abstract Background Proteolytic imbalance has been described in patients with inflammatory bowel disease (IBD) and in different models of experimental colitis. Although the proteases reported to be increased are mainly from the host, the role of bacterial proteases has recently emerged, as they can promote inflammation, in part, through activation of Protease-activated receptors (PARs). PAR2 deficient mice are resistant to inflammation and PAR2 activation affects multiple aspects of the tissue response to injury. However, PAR2 communicates with other receptors such as toll-like and other PARs, which are important in multiple immune signaling pathways. Thus, the direct implication of PAR2 in…

Biochemistry and medicinal chemistry of the dengue virus protease.

2014

Synthesis of C3/C1-Substituted Tetrahydroisoquinolines

2015

A broad biological screening of the natural alkaloid N-methylisosalsoline (2) extracted from Hammada scoparia leaves against a panel of human and parasitic proteases revealed an interesting activity profile of 2 towards human 20S proteasome. This outcome suggests that the 1,2,3,4-tetrahydroisoquinoline skeleton may be exploited as a template for the development of novel anticancer agents. In this article, we report the synthesis and chemical characterization of a new series of isosalsoline-type alkaloids (10-11) with variations at N2 and C3 positions with respect to the natural Compound 2, obtained by a synthetic strategy that involves the Bischler-Napieralski cyclization. The substrate for…

Characterization of EprA, a major extracellular protein of Oenococcus oeni with protease activity

2008

International audience; Extracellular proteins from Oenococcus oeni. a wine-making bacterium, were isolated during growth on media differing by their nitrogen content. Analysis by two-dimensional electrophoresis revealed a low number of protein signals. Among the main spots, one signal corresponded to a single protein, which contained a lysine repeat domain characteristic of cell-wall hydrolases. We demonstrated that this major protein, named EprA, was able to hydrolyse several proteins. The heterologous production of this protein in Escherichia coli confirmed the protease activity of EprA. With a MW of 21.3 kDa and a pl of 5.3, EprA presents optimal activity at pH 7.0 and 45 degrees C. Thi…

Proline-Based Allosteric Inhibitors of Zika and Dengue Virus NS2B/NS3 Proteases

2019

The NS2B/NS3 serine proteases of the Zika and Dengue flaviviruses are attractive targets for the development of antiviral drugs. We report the synthesis and evaluation of a new, proline-based compound class that displays allosteric inhibition of both proteases. The structural features relevant for protease binding and inhibition were determined to establish them as new lead compounds for flaviviral inhibitors. Based on our structure-activity relationship studies, the molecules were further optimized, leading to inhibitors with submicromolar IC50 values and improved lipophilic ligand efficiency. The allosteric binding site in the proteases was probed using mutagenesis and covalent modificati…

Mitochondrial and cytoplasmic protease activity in sea urchin eggs

1957

The apoptotic effects and synergistic interaction of sodium butyrate and MG132 in human retinoblastoma Y79 cells

1999

This study deals with the apoptotic effect exerted on human retinoblastoma Y79 cells by both sodium butyrate and an inhibitor of 26S proteasome [z-Leu-Leu-Leu-CHO (MG132)] and their synergistic effect. Exposure to sodium butyrate (1-4 mM) induced an accumulation of cells in the G2-M phase that was already visible after 24 h of treatment, when morphological and biochemical signs of apoptosis appeared only in a small number of cells (5-10%). Thereafter, the apoptotic effects increased progressively with slow kinetics, reaching a maximum after 72 h of exposure, when they concerned a large fraction of cells (>75% with 4 mM sodium butyrate). Sodium butyrate stimulated the conversion of procaspas…

Bioorganic/inorganic hybrid composition of sponge spicules: matrix of the giant spicules and of the comitalia of the deep sea hexactinellid Monorhaph…

2007

The giant basal spicules of the siliceous sponges Monorhaphis chuni and Monorhaphis intermedia (Hexactinellida) represent the largest biosilica structures on earth (up to 3 m long). Here we describe the construction (lamellar organization) of these spicules and of the comitalia and highlight their organic matrix in order to understand their mechanical properties. The spicules display three distinct regions built of biosilica: (i) the outer lamellar zone (radius: >300 mu m), (ii) the bulky axial cylinder (radius: <75 mu m), and (iii) the central axial canal (diameter: <2 mu m) with its organic axial filament. The spicules are loosely covered with a collagen net which is regularly perforated …