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1.
T. V. Fedorov V. I. Korobov V. G. Nazarov A. E. Smolkina V. A. Shmelev 《Applied Biochemistry and Microbiology》2010,46(2):226-229
Hybrid protein, cancer necrosis factor thymosin-α1 (TNF-T), when synthesizing in strain-producer of Escherichia coli SG200-50 with plasmid pThy315, was a part of “inclusion bodies” mostly in the form of a high-molecular complex with other proteins due to the S-S bonds formation. An approach of purification of TNF-T has been proposed, which is based on the destruction of the complex in the presence of sodium dodecylsulfate (DDS-Na) and dithiotreitol (DDT) followed by gel-filtration on Sephadex G-100 and renaturation by ultrafiltration on hollow fibers. The method allows the isolation of electrophoretically homogeneous TNF-T containing no DDS-Na and having high cytotoxic activity against cancer cells of mouse adenocarcinome L-929. The yield of TNF-T achieved 80% relative its content in biomass and 30% relative the total protein. 相似文献
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Viktor Patzelt 《Cell and tissue research》1955,41(5):460-473
Zusammenfassung Aus dieser neuerlichen Untersuchung der zuerst von Stilling beschriebenen Sommerzellen ergibt sich somit als einzige Übereinstimmung in den sonst widerspruchsvollen Angaben des Schrifttums, daß sie in ihrem Vorkommen nicht auf den Sommer beschränkt sind, weshalb sie von mir nach ihrer färberischen Eigentümlichkeit als chromotrope Zellen bezeichnet werden. Da ihr isoelektrischer Punkt bei etwa pH 5 liegt, verhalten sie sich gegenüber Farbstoffen nicht ausschließlich (acido-) oxyphil, doch sind sie auch keine Mastzellen oder überhaupt während der Entwicklung veränderte Wanderzellen, sondern eine besondere Art autochthon entstandener Nebennieren-Epithelzellen, deren Körnchen saure Polysaccharide enthalten. Ihre funktionelle Bedeutung muß erst geklärt werden. Dabei ist es besonders bemerkenswert, daß sich das Vorkommen dieser Zellen auf Rana esculenta und eine Abart von ihr sowie exotische Verwandte beschränkt, während sie bei Rana temporaria und deren nächsten Verwandten immer fehlen. Die gegenteiligen Angaben der Literatur beruhen wahrscheinlich teilweise auf unzutreffender Bestimmung der Art und im übrigen wohl auf Verwechslung mit gekörnten Wanderzellen, was besonders bei der Entwicklung zu falschen Vorstellungen führen kann.Herrn Professor Alfred Kohn in dankbarer Erinnerung gewidmet. 相似文献
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The natural abundance 15N nmr spectra of linear polysarcosine (DP = 35) has been recorded in Me2SO and H2O solution. Because of cis/trans isomerization at the peptide bond, a broad signal with several splittings was observed. These splittings appear to reflect the influence of three peptide bonds on a single N atom. The 15N signals from the sequence polypeptides (β-Ala-Sar-Gly)n and (β-Ala-Sar-D ,L -Ala)n also show a cis/trans splitting, as well as chemical shifts which are dependent on the peptide sequence. The tertiary nitrogen of the sarcosyl residue has a T1 relaxation time which is longer than the T1 for secondary nitrogens of the other amino acids. The nuclear Overhauser effect is also discussed. 相似文献
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Sailendra N. Nichenametla Dwight A. L. Mattocks Diana Cooke Vishal Midya Virginia L. Malloy Wilfredo Mansilla Bente
vreb Cheryl Turner Nasser
E. Bastani Jitka Sokolov Markta Pavlíkov John P. Richie Jr. Anna
K. Shoveller Helga Refsum Thomas Olsen Kathrine J. Vinknes Viktor Koich Gene P. Ables 《Aging cell》2022,21(12)
Decreasing the dietary intake of methionine exerts robust anti‐adiposity effects in rodents but modest effects in humans. Since cysteine can be synthesized from methionine, animal diets are formulated by decreasing methionine and eliminating cysteine. Such diets exert both methionine restriction (MR) and cysteine restriction (CR), that is, sulfur amino acid restriction (SAAR). Contrarily, SAAR diets formulated for human consumption included cysteine, and thus might have exerted only MR. Epidemiological studies positively correlate body adiposity with plasma cysteine but not methionine, suggesting that CR, but not MR, is responsible for the anti‐adiposity effects of SAAR. Whether this is true, and, if so, the underlying mechanisms are unknown. Using methionine‐ and cysteine‐titrated diets, we demonstrate that the anti‐adiposity effects of SAAR are due to CR. Data indicate that CR increases serinogenesis (serine biosynthesis from non‐glucose substrates) by diverting substrates from glyceroneogenesis, which is essential for fatty acid reesterification and triglyceride synthesis. Molecular data suggest that CR depletes hepatic glutathione and induces Nrf2 and its downstream targets Phgdh (the serine biosynthetic enzyme) and Pepck‐M. In mice, the magnitude of SAAR‐induced changes in molecular markers depended on dietary fat concentration (60% fat >10% fat), sex (males > females), and age‐at‐onset (young > adult). Our findings are translationally relevant as we found negative and positive correlations of plasma serine and cysteine, respectively, with triglycerides and metabolic syndrome criteria in a cross‐sectional epidemiological study. Controlled feeding of low‐SAA, high‐polyunsaturated fatty acid diets increased plasma serine in humans. Serinogenesis might be a target for treating hypertriglyceridemia. 相似文献
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Viktor Stabnikov Chu Jian Volodymyr Ivanov Yishan Li 《World journal of microbiology & biotechnology》2013,29(8):1453-1460
Microbially induced calcium carbonate precipitation (MICP) is a phenomenon based on urease activity of halotolerant and alkaliphilic microorganisms that can be used for the soil bioclogging and biocementation in geotechnical engineering. However, enrichment cultures produced from indigenous soil bacteria cannot be used for large-scale MICP because their urease activity decreased with the rate about 5 % per one generation. To ensure stability of urease activity in biocement, halotolerant and alkaliphilic strains of urease-producing bacteria for soil biocementation were isolated from either sandy soil or high salinity water in different climate zones. The strain Bacillus sp. VUK5, isolated from soil in Ukraine (continental climate), was phylogenetically close in identity (99 % of 16S rRNA gene sequence) to the strain of Bacillus sp. VS1 isolated from beach sand in Singapore (tropical rainforest climate), as well as to the strains of Bacillus sp. isolated by other researchers in Ghent, Belgium (maritime temperate climate) and Yogyakarta, Indonesia (tropical rainforest climate). Both strains Bacillus sp. VS1 and VUK5 had maximum specific growth rate of 0.09/h and maximum urease activities of 6.2 and 8.8 mM of hydrolysed urea/min, respectively. The halotolerant and alkaliphilic strain of urease-producing bacteria isolated from water of the saline lake Dead Sea in Jordan was presented by Gram-positive cocci close to the species Staphylococcus succinus. However, the strains of this species could be hemolytic and toxigenic, therefore only representatives of alkaliphilic Bacillus sp. were used for the biocementation studies. Unconfined compressive strengths for dry biocemented sand samples after six batch treatments with strains VS1and VUK5 were 765 and 845 kPa, respectively. The content of precipitated calcium and the strength of dry biocemented sand at permeability equals to 1 % of initial value were 12.4 g Ca/kg of dry sand and 454 kPa, respectively, in case of biocementation by the strain VS1. So, halotolerant, alkaliphilic, urease-producing bacteria isolated from different climate zones have similar properties and can be used for biocementation of soil. 相似文献
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Eliza F. Chakravarty Viktor Martyanov David Fiorentino Tammara A. Wood David James Haddon Justin Ansel Jarrell Paul J. Utz Mark C. Genovese Michael L. Whitfield Lorinda Chung 《Arthritis research & therapy》2015,17(1)
IntroductionSystemic sclerosis is an autoimmune disease characterized by inflammation and fibrosis of the skin and internal organs. We sought to assess the clinical and molecular effects associated with response to intravenous abatacept in patients with diffuse cutaneous systemic.MethodsAdult diffuse cutaneous systemic sclerosis patients were randomized in a 2:1 double-blinded fashion to receive abatacept or placebo over 24 weeks. Primary outcomes were safety and the change in modified Rodnan Skin Score (mRSS) at week 24 compared with baseline. Improvers were defined as patients with a decrease in mRSS of ≥30 % post-treatment compared to baseline. Skin biopsies were obtained for differential gene expression and pathway enrichment analyses and intrinsic gene expression subset assignment.ResultsTen subjects were randomized to abatacept (n = 7) or placebo (n = 3). Disease duration from first non-Raynaud’s symptom was significantly longer (8.8 ± 3.8 years vs. 2.4 ± 1.6 years, p = 0.004) and median mRSS was higher (30 vs. 22, p = 0.05) in the placebo compared to abatacept group. Adverse events were similar in the two groups. Five out of seven patients (71 %) randomized to abatacept and one out of three patients (33 %) randomized to placebo experienced ≥30 % improvement in skin score. Subjects receiving abatacept showed a trend toward improvement in mRSS at week 24 (−8.6 ± 7.5, p = 0.0625) while those in the placebo group did not (−2.3 ± 15, p = 0.75). After adjusting for disease duration, mRSS significantly improved in the abatacept compared with the placebo group (abatacept vs. placebo mRSS decrease estimate −9.8, 95 % confidence interval −16.7 to −3.0, p = 0.0114). In the abatacept group, the patients in the inflammatory intrinsic subset showed a trend toward greater improvement in skin score at 24 weeks compared with the patients in the normal-like intrinsic subset (−13.5 ± 3.1 vs. −4.5 ± 6.4, p = 0.067). Abatacept resulted in decreased CD28 co-stimulatory gene expression in improvers consistent with its mechanism of action. Improvers mapped to the inflammatory intrinsic subset and showed decreased gene expression in inflammatory pathways, while non-improver and placebos showed stable or reverse gene expression over 24 weeks.ConclusionsClinical improvement following abatacept therapy was associated with modulation of inflammatory pathways in skin.
Trial registration
ClinicalTrials.gov . Registered 1 March 2007. NCT00442611Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0669-3) contains supplementary material, which is available to authorized users. 相似文献9.
Svetlana N. Kovalchuk Irina Yu. Bakunina Viktor I. Emelyanenko Konstantin V. Guzev Valeri A. Rasskazov 《Carbohydrate research》2009,344(2):191-252
An endo-(1→3)-β-d-glucanase (L0) with molecular mass of 37 kDa was purified to homogeneity from the crystalline style of the scallop Chlamys albidus. The endo-(1→3)-β-d-glucanase was extremely thermolabile with a half-life of 10 min at 37 °C. L0 hydrolyzed laminaran with Km ∼ 0.75 mg/mL, and catalyzed effectively transglycosylation reactions with laminaran as donor and p-nitrophenyl β d-glucoside as acceptor (Km ∼ 2 mg/mL for laminaran) and laminaran as donor and as acceptor (Km ∼ 5 mg/mL) yielding p-nitrophenyl β d-glucooligosaccharides (n = 2-6) and high-molecular branching (1→3),(1→6)-β-d-glucans, respectively. Efficiency of hydrolysis and transglycosylation processes depended on the substrate structure and decreased appreciably with the increase of the percentage of β-(1→6)-glycosidic bonds, and laminaran with 10% of β-(1→6)-glycosidic bonds was the optimal substrate for both reactions. The CD spectrum of L0 was characteristic for a protein with prevailing β secondary-structural elements. Binding L0 with d-glucose as the best acceptor for transglycosylation was investigated by the methods of intrinsic tryptophan fluorescence and CD. Glucose in concentration sufficient to saturate the enzyme binding sites resulted in a red shift in the maximum of fluorescence emission of 1-1.5 nm and quenching the Trp fluorescence up to 50%. An apparent association constant of L0 with glucose (Ka = 7.4 × 105 ± 1.1 × 105 M−1) and stoichiometry (n = 13.3 ± 0.7) was calculated. The cDNA encoding L0 was sequenced, and the enzyme was classified in glycoside hydrolases family 16 on the basis of the amino acid sequence similarity. 相似文献
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