10 research outputs found
Formation of resilience, ecocentric worldview, conscious citizenship for the purpose of physical improvement and patriotic education of teenage athletes
The author of the article, using the example of the formative environment of the Olympic Reserve school, examines the issues of the development of resilience and conscious citizenship as the most significant qualities for physical improvement and patriotic education of adolescent athletes. In the difficult conditions of Russia’s international cooperation with Western countries, physical improvement and patriotic education are considered as two main vectors of training young athletes. According to the author, the basic personal qualities of the successful development of these target areas in the conditions of the Olympic reserve school, respectively, can be the resilience and conscious citizenship of students
Bioconversion of Airborne Methylamine by Immobilized Recombinant Amine Oxidase from the Thermotolerant Yeast Hansenula polymorpha
Aliphatic amines, including methylamine, are air-pollutants, due to their intensive use in industry and the natural degradation of proteins, amino acids, and other nitrogen-containing compounds in biological samples. It is necessary to develop systems for removal of methylamine from the air, since airborne methylamine has a negative effect on human health. The primary amine oxidase (primary amine : oxygen oxidoreductase (deaminating) or amine oxidase, AMO; EC 1.4.3.21), a copper-containing enzyme from the thermotolerant yeast Hansenula polymorpha which was overexpressed in baker’s yeast Saccharomyces cerevisiae, was tested for its ability to oxidize airborne methylamine. A continuous fluidized bed bioreactor (CFBR) was designed to enable bioconversion of airborne methylamine by AMO immobilized in calcium alginate (CA) beads. The results demonstrated that the bioreactor with immobilized AMO eliminates nearly 97% of the airborne methylamine. However, the enzymatic activity of AMO causes formation of formaldehyde. A two-step bioconversion process was therefore proposed. In the first step, airborne methylamine was fed into a CFBR which contained immobilized AMO. In the second step, the gas flow was passed through another CFBR, with alcohol oxidase from the yeast H. polymorpha immobilized in CA, in order to decompose the formaldehyde formed in the first step. The proposed system provided almost total elimination of the airborne methylamine and the formaldehyde
Environmental compliance and business strategies practices of entrepreneurial ventures
The study is devoted to the research of environmental compliance and business strategies of the practice of venture enterprises. The purpose of the study is to determine the role of environmental compliance in the business strategies of enterprises and to reveal the potential of a positive impact on sustainable development. The paper examines hypotheses regarding the favourable impact of environmental compliance on the competitiveness and innovative potential of enterprises. Environmental compliance and business strategies of enterprises have the potential to promote sustainable environmental development, which is currently only 10% used. This requires the active participation of enterprises in the implementation of environmental practices, investments in innovative solutions and the development of knowledge. The study highlights the need to support and promote practices such as venture entrepreneurship, which contribute to the creation of new environmentally relevant technologies, products and services. Therefore, the results of this work indicate the importance of developing and implementing ecologically appropriate business strategies in business practices. This can contribute to improving the environmental condition, ensuring sustainable development and strengthening the competitive positions of national economies
Cdk1-mediated threonine phosphorylation of Sam68 modulates its RNA binding, alternative splicing activity and cellular functions
Sam68, also known as KHDRBS1, is a member of the STAR family of proteins that directly link signal transduction with post-transcriptional gene regulation. Sam68 controls the alternative splicing of many oncogenic proteins and its role is modulated by post-translational modifications, including serine/threonine phosphorylation, that differ at various stages of the cell cycle. However, the molecular basis and mechanisms of these modulations remain largely unknown. Here, we combined mass spectrometry, nuclear magnetic resonance spectroscopy and cell biology techniques to provide a comprehensive post-translational modification mapping of Sam68 at different stages of the cell cycle in HEK293 and HCT116 cells. We established that Sam68 is specifically phosphorylated at T33 and T317 by Cdk1, and demonstrated that these phosphorylation events reduce the binding of Sam68 to RNA, control its cellular localization and reduce its alternative splicing activity, leading to a reduction in the induction of apoptosis and an increase in the proliferation of HCT116 cells
Structural basis of RNA recognition and dimerization by the STAR proteins T-STAR and Sam68
Sam68 and T-STAR are members of the STAR family of proteins that directly link signal transduction with post-transcriptional gene regulation. Sam68 controls the alternative splicing of many oncogenic proteins. T-STAR is a tissue-specific paralogue that regulates the alternative splicing of neuronal pre-mRNAs. STAR proteins differ from most splicing factors, in that they contain a single RNA-binding domain. Their specificity of RNA recognition is thought to arise from their property to homodimerize, but how dimerization influences their function remains unknown. Here, we establish at atomic resolution how T-STAR and Sam68 bind to RNA, revealing an unexpected mode of dimerization different from other members of the STAR family. We further demonstrate that this unique dimerization interface is crucial for their biological activity in splicing regulation, and suggest that the increased RNA affinity through dimer formation is a crucial parameter enabling these proteins to select their functional targets within the transcriptome
Interconnections between transcription and pre-mRNA splicing
Eukaryotic gene expression involves many processes some of which are transcription and pre-mRNA splicing. It has been shown that the majority of splicing events are functionally or physically coupled to RNA polymerase II transcription machinery. This suggests that transcription and splicing processes might influence one another. For example, a number of studies have implicated snRNPs, in particular U1 snRNP, in transcription initiation and elongation. In this work, interconnections between transcription and splicing were tested using an in vitro RNA polymerase II transcription/splicing assays (Pol II-TSRs). The results obtained in this study showed that inhibition of U1 but not U2 or U6 snRNPs led to a major reduction in transcript levels using different DNA templates. However, interference with initiation was excluded because it was found that this effect was the result of reduced RNA stability.
Moreover, similar results were observed both with transcription by T7 RNA polymerase and with purified transcripts added to the extract. These results allow to conclude that the U1 snRNP has a novel function in protecting RNA from degradation. Further investigations showed that the RNA is protected by the U1 snRNP against 5’ exonucleases and 3’ exonucleases and possibly endonucleases. It was found that the presence of 5’ splice site (5’SS) is necessary for RNA stability. These data suggest that the U1 snRNP through a direct interaction with the 5’SS of the pre-mRNA protects it from degradation and only U1 snRNP but not the active spliceosome is required for RNA stability. It was observed that under splicing conditions, the RNA level of a transcript lacking the intronic consensus 5’SS but having it at the 3’ end was significantly higher compared to that for a transcript lacking any consensus 5’SSs, suggesting that the U1 snRNP protects transcripts from degradation along their length. It is proposed that rapid binding of the U1 snRNPs to the nascent transcripts induces the assembly of RNA binding proteins that protect the RNA. Interestingly, any transcripts tested regardless of the presence of the consensus 5’SSs were stable in the reaction with ongoing transcription, suggesting that Pol II transcription has an additional effect on RNA stability
Highly selective apo-arginase based method for sensitive enzymatic assay of manganese (II) and cobalt (II) ions
International audienceA novel enzymatic method of manganese (II) and cobalt (II) ions assay, based on using apo-enzyme of Mn2+-dependent recombinant arginase I (arginase) and 2,3-butanedione monoxime (DMO) as a chemical reagent is proposed. The principle of the method is the evaluation of the activity of L-arginine-hydrolyzing of arginase holoenzyme after the specific binding of Mn2+ or Co2+ with apo-arginase. Urea, which is the product of enzymatic hydrolysis of L-arginine (Arg), reacts with DMO and the resulted compound is detected by both fluorometry and visual spectrophotometry. Thus, the content of metal ions in the tested samples can be determined by measuring the level of urea generated after enzymatic hydrolysis of Arg by reconstructed arginase holoenzyme in the presence of tested metal ions. The linearity range of the fluorometric apo-arginase-DMO method in the case of Mn2+ assay is from 4pM to 1.10nM with a limit of detection of 1pM Mn2+, whereas the linearity range of the present method in the case of Co2+ assay is from 8pM to 45nM with a limit of detection of 2.5pM Co2+. The proposed method being highly sensitive, selective, valid and low-cost, may be useful to monitor Mn2+ and Co2+ content in clinical laboratories, food industry and environmental control service
Methylamine-Sensitive Amperometric Biosensor Based on (His)6-Tagged Hansenula polymorpha Methylamine Oxidase Immobilized on the Gold Nanoparticles
A novel methylamine-selective amperometric bienzyme biosensor based on recombinant primary amine oxidase isolated from the recombinant yeast strain Saccharomyces cerevisiae and commercial horseradish peroxidase is described. Two amine oxidase preparations were used: free enzyme (AMO) and covalently immobilized on the surface of gold nanoparticles (AMO-nAu). Some bioanalytical parameters (sensitivity, selectivity, and storage stability) of the developed biosensors were investigated. The sensitivity for both sensors is high: 1450 ± 113 and 700 ± 30 A−1·M−1·m−2 for AMO-nAu biosensor, respectively. The biosensors exhibit the linear range from 15 μM to 150 μM (AMO-nAu) and from 15 μM to 60 μM (AMO). The developed biosensor demonstrated a good selectivity toward methylamine (MA) (signal for dimethylamine and trimethylamine is less than 5% and for ethylamine 15% compared to MA output) and reveals a satisfactory storage stability. The constructed amperometric biosensor was used for MA assay in real samples of fish products in comparison with chemical method. The values obtained with both approaches different methods demonstrated a high correlation
Highly Sensitive Amperometric Biosensors Based on Oxidases and CuCe Nanoparticles Coupled with Porous Gold
Metallic nanoparticles are usually applied in biosensors as catalysts and/or mediators of electron transfer. We describe the development of amperometric biosensors (ABSs) based on oxidases and nanoparticles of CuCe (nCuCe). nCuCe, being an electro-active mediator and active peroxidase (PO) mimetic, was used as an H2O2-sensing platform in oxidase-based ABSs. ABSs for glucose, primary alcohols, methyl amine, catechol, and L-arginine, which are based on corresponding oxidases and nCuCe, were developed. These ABSs exhibited improved analytical characteristics in comparison with the appropriate bi-enzyme ABSs containing natural PO. Including electrodeposited porous gold in the chemo-sensing layer was shown to increase significantly the sensitivities of all constructed ABSs