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Недостаток вложения вируса Рабиуса Гликпротеина в вирионы усиливает вирусную эвакуацию и вирусную патогенность.

Предыдущие исследования показали, что вирус диких (wt) бешенств (RABV) избегает иммунной реакции принимающей стороны, ограничивая выражение гликпротеина (G), который блокирует активацию дендритных клеток (DC) и стимулирует производство антител, нейтрализующих вирусы (VNA). В настоящем исследовании Wt RABVs не только ограничили выражение G, но и сократили охват G зрелыми вирионами по сравнению с лабораторными вирусами. Рекомбинантная RABV, выражающая тройную G, была использована для дальнейшего определения того, связано ли выражение G с инкорпорацией. Рекомбинантный вирус показал более высокое

Совпадение в аннотации оригинала
Previous studies have shown that wild-type (wt) rabies virus (RABV) evades the host immune response by restricting expression of glycoprotei … DCs than the virus that expressed a single copy of G. Removal of G from viruses using subtilisin or Dithiothreitol (DTT)/ Nonidet P-40 (NP40) almost completely abolishes DC activation and VNA production. Consequently, these G-depleted viruses cause lethal infection in mice. Thus, wt RABVs can subvert DC-induced antiviral immune response and maintain pathogenicit …

Label-free peptide aptamer based impedimetric biosensor for highly sensitive detection of TNT with a ternary assembly layer.

We report a label-free peptide aptamer based biosensor for highly sensitive detection of TNT which was designed with a ternary assembly layer consisting of anti-TNT peptide aptamer (peptamer), dithiothreitol (DTT), and 6-mercaptohexanol (MCH), forming Au/peptamer-DTT/MCH. A linear relationship between the change in electron transfer resistance and the logarithm of the TNT concentration from 0.44 to 18.92 pM, with a detection limit of 0.15 pM, was obtained. In comparison, the detection limit of the aptasensor with a common binary assembly layer (Au/peptamer/MCH) was 0.15 nM. The remarkable impr…

Overexpression, crystallization and preliminary X-ray crystallographic analysis of Pseudomonas aeruginosa MnmE, a GTPase involved in tRNA modification.

MnmE, an evolutionarily conserved GTPase, is involved in modification of the uridine base (U34) at the wobble position of certain tRNAs. Pre … DA pH 6.5, 12%(w/v) polyethylene glycol 4000, 100 mM lithium sulfate, 2%(v/v) 2-propanol and 2.5 mM dithiothreitol. X-ray diffraction data were collected to 2.69 A resolution. The crystals belonged to the orthorhombic space group C222(1), with unit-cell parameters a=96.74, b=204.66, c=120.90 A. Two monomers were present in the asymmetric unit, resulting in a cry …

The novel metalloproteinase atroxlysin-I from Peruvian Bothrops atrox (Jergón) snake venom acts both on blood vessel ECM and platelets.

We report the isolation and structure-function relationship of a 23kDa metalloproteinase named atroxlysin-I from the venom of the Peruvian Bothrops atrox (Jergón). Atroxlysin is a P-I metalloproteinase and contains 204 residues. Its proteolytic activity towards dimethylcasein is enhanced by Ca2+ but inhibited by EDTA, dithiothreitol, excessive Zn2+ and alpha2-macroglobulin. Unlike other structurally homologous P-I metalloproteinases, atroxlysin-I causes hemorrhages. To examine its hemorrhagic activity mechanistically, we studied its function in vitro and in vivo. It cleaved the Ala14-Leu15 and…

Purification and biochemical characterization of polyphenol oxidases from embryogenic and nonembryogenic cotton (Gossypium hirsutum L.) cells.

Polyphenol oxidases (PPOs) were isolated from cell suspensions of two cultivars of cotton (Gossypium hirsutum L.), and their biochemical cha … grees C and was relatively stable at 20-30 degrees C. Reducing sodium metabisulfite, ascorbic acid, dithiothreitol, SnCl(2), and FeCl(3) markedly inhibited PPO activity, whereas its activity was highly enhanced by Mg(2+), Ca(2+), and Mn(2+) and was moderately inhibited by Ba(2+), Cu(2+), and Zn(2+). The analysis revealed a single band on the sodium dodecyl sulfa …

Glutamate uptake is reduced in prefrontal cortex in Huntington's disease.

Huntington's disease (HD) is caused by a CAG repeat expansion in the HD gene, but how this mutation causes neuronal dysfunction and degenera … amate uptake correlated inversely with CAG repeat expansion (r= -0.82, p=0.015). The reducing agent dithiothreitol improved glutamate uptake in controls, but not in HD brains, suggesting irreversible oxidation of glutamate transporters in HD. We conclude that impairment of glutamate uptake may contribute to neuronal dysfunction and degeneration in HD.

Isolation and characterization of a novel elastase inhibitor, AFLEI from Aspergillus flavus.

A novel elastase inhibitor from Aspergillus flavus (AFLEI) was isolated, and biochemical properties of AFLEI were examined. Column chromatog … cetic acid (EDTA-2Na), benzamidine, chymostatin, tosyl phenylalanine chloromethyl ketone (TPCK) and dithiothreitol (DTT) did not show any inhibitory effect on the elastase inhibitory activity of AFLEI.

Refilling of ocular lens capsule with copolymeric hydrogel containing reversible disulfide.

Polymer solutions can fill any potential irregular cavity using minimally invasive techniques and thus have potential uses in ophthalmology. We prepared acrylamide hydrogels containing disulfide bonds by free radical polymerization in aqueous ethanol. The hydrogels were liquefied using dithiothreitol to yield water-soluble acrylamide copolymers containing pendant thiol (-SH) groups. The weight average molecular weights of the copolymers ranged from 1.43 x 10(5) to 9.22 x 10(5) daltons by GPC. Ellman's analysis and Raman spectroscopy confirmed the presence of -SH. The aqueous solutions of these…

Suppression of urease levels in Streptococcus salivarius by cysteine, related compounds and by sulfide.

Urease synthesis in Streptococcus salivarius is induced by an acid environment, carbohydrate and a high growth rate. We now report that both cysteine and sulfide above 1 mM strongly suppress S. salivarius urease levels. Close structural relatives of cysteine (cysteamine, ethanedithiol and penicillamine) at 5 mM buffered to pH 7.0 also caused urease suppression, but thiols in general (2-mercaptoethanol, dithiothreitol and glutathione) did not. In cultures buffered below pH 5.9, the cysteine-induced urease suppression was lifted substantially, but the sulfide suppression increased, suggesting in…

A neutral cysteine protease of Spirometra mansoni plerocercoid invoking an IgE response.

When crude extracts of Spirometra mansoni plerocercoid (sparganum) were analysed by SDS-polyacrylamide gel electrophoresis (PAGE)/immunoblot … succinyl-L- leucylamido-(4-guanidino)butane (E-64) and 1 mM iodoacetamide (IAA), and potentiated by dithiothreitol (DTT, 5 mM).

Elevation of intracellular Ca2+ concentration in rabbit nonpigmented ciliary epithelial cells by allicin.

A previous study has shown that allicin produces changes in aqueous humor dynamics, and this study was conducted to examine possible cellular mechanisms. In rabbit nonpigmented ciliary epithelial cells, basal levels of [Ca2+]i were determined to be 164 +/- 34 nM. Allicin, a sulfhydryl-reactive agent, induced Ca2+ transients at 0.01 mM and at 0.2 mM, the Ca2+ transient peaked at 732 +/- 35 nM. Allicin-induced Ca2+ transients were prevented by pretreatment with dithiothreitol which did not affect the basal Ca2+ levels. Allicin had only a slight, insignificant, effect on L-type Ca2+ currents, and…

Effects of the state of the succinimido-ring on the fluorescence and structural properties of pyrene maleimide-labeled alpha alpha-tropomyosin.

Rabbit skeletal alpha alpha-tropomyosin was labeled at Cys-190 with pyrene maleimide to form (S-[N-(1-pyrene)succinimido])2-tropomyosin (pyr … ends of tropomyosin. The fluorescence properties of the two types of pyrene-succinimide adducts of dithiothreitol were very similar to the corresponding adducts of pyrene-Tm indicating excimer formation through ground state pyrene-pyrene interaction.

Kinetics of carbamylcholine binding to membrane-bound acetylcholine receptor monitored by fluorescence changes of a covalently bound probe.

The fluorescent probe 5-(iodoacetamido)salicylic acid has been used to alkylate acetylcholine receptor enriched membrane fragments from Torpedo californica following their reduction with low concentrations of dithiothreitol. This modification did not affect the equilibrium binding of carbamylcholine to the receptor. The fluorescence of bound 5-(iodoacetamido)salicyclic acid was enhanced when the labeled membrane fragments were mixed with carbamylcholine. This increase in fluorescence was abolished by preincubation of the membrane fragments with excess alpha-bungarotoxin and was therefore speci…

Red-cell-membrane polypeptide aggregates in glucose-6-phosphate dehydrogenase mutants with chronic hemolytic disease. A clue to the mechanism of hemolysis.

Red-cell membranes from patients with glucose-6-phosphate dehydrogenase deficiency were studied with polyacrylamide gel electrophoresis and … found in appreciable amounts in these cells. The aggregates were dissociated by mercaptoethanol or dithiothreitol -- indicating that they were formed by intermolecular disulfide bonds. The polypeptide aggregates contained spectrin but not globin. Red-cell deformability was decreased in aggregate-containing cells. We postulate that the polypeptide aggregates are …

Application of the capillary electrophoresis method for the study of plasma proteins homocysteinylation.

PURPOSE: Purpose. This article describes the use of capillary electrophoresis with UV detection to determine the ratio of protein-bound homocysteine and cysteine concentrations in human plasma. METHODS: Plasma samples were reduced with dithiothreitol and derivatized by thiocarbonyldiimidazole before being filtered again for purification of proteins. The pre-concentration of analytes was carried out directly in the capillary (48.5 cm in length and an inner diameter of 50 mkm) by NaOH post-injection. The eletrophoretic separation of analytes was carried out using 0.2 M ammonium acetate with 25 …

Calcineurin activity is regulated both by redox compounds and by mutant familial amyotrophic lateral sclerosis-superoxide dismutase.

Calcineurin (CN) is a protein phosphatase involved in a wide range of cellular responses to calcium-mobilizing signals, and a role for this enzyme in neuropathology has been postulated. We have investigated the possibility that redox modulation of CN activity is relevant to neuropathological conditions where an imbalance in reactive oxygen species has been described. We have monitored CN activity in cultured human neuroblastoma SH-SY5Y cells and obtained evidence that CN activity is promoted by treatment with ascorbate or dithiothreitol and impaired by oxidative stress. Evidence for the existe…

Thiol-group reactivity, hydrophilicity and stability of alloxan, its reduction products and its N-methyl derivatives and a comparison with ninhydrin.

The diabetogenic agent, alloxan, is a hydrophilic and chemically unstable compound. The logarithm of the octanol/water partition coefficient … however, with ninhydrin. Comparatively slow redox cycling was recorded with alloxan derivatives and dithiothreitol although rapid cycling occurred with ninhydrin and this dithiol. Such differences may explain why ninhydrin does not share with alloxan a selective toxic effect upon the pancreatic B-cell.

Glutamine synthetase activity of developing astrocytes is inhibited in vitro by very low concentrations of lead.

This study has dealt with the inhibition by lead of glutamine synthetase (GS) activity in homogenates of mixed glial primary cultures, 95% enriched in differentiating astrocytes. A 70% inhibition was observed with a lead concentration of only 2.5 microM. Prevention of the inhibition by addition of EDTA or dithiothreitol is compatible with the conclusion that the effect is mediated by binding of lead ion to sulfhydryl moieties of the enzyme. Among several other cations tested, only mercury, which has a similarly high binding affinity for sulfhydryl moieties, inhibited the enzyme. The inhibitory…

Inactivation of liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase by o-phthalaldehyde.

The two activities of chicken liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase were inactivated by o-phthalaldehyde. Absorbance an … te fully protected against o-phthalaldehyde-induced inactivation of the bisphosphatase. Addition of dithiothreitol prevented both the increase in fluorescence and the inactivation of fructose-2,6-bisphosphatase, but not that of 6-phosphofructo-2-kinase. It is proposed that o-phthalaldehyde forms two different inhibitory adducts: a non-fluorescent adduct in the k …

A simple phenol-free isolation method for high-quality RNA from bilberry.

High-quality RNA is required for accurate gene expression and transcriptome analysis. The current methods of RNA extraction from berry fruits are either time-consuming or expensive. To simplify the conventional phenol-chloroform based RNA extraction method, we modified the protocol with less steps as well as the removal of the use of phenol. In this protocol, the extraction buffer is composed of hexadecyltrimethyl ammonium bromide (CTAB), polyvinylpyrrolidone (PVP), and Dithiothreitol (DTT). The method facilitates efficient removal of polysaccharides and phenolic compounds from both fruit pulp…