Abstract
Despite their very close structural similarity, CxxC/S-type (class I) glutaredoxins (Grxs) act as oxidoreductases, while CGFS-type (class II) Grxs act as FeS cluster transferases. Here we ...show that the key determinant of Grx function is a distinct loop structure adjacent to the active site. Engineering of a CxxC/S-type Grx with a CGFS-type loop switched its function from oxidoreductase to FeS transferase. Engineering of a CGFS-type Grx with a CxxC/S-type loop abolished FeS transferase activity and activated the oxidative half reaction of the oxidoreductase. The reductive half-reaction, requiring the interaction with a second GSH molecule, was enabled by switching additional residues in the active site. We explain how subtle structural differences, mostly depending on the structure of one particular loop, act in concert to determine Grx function.
The recent statistics on Agriculture identically remarks the massive contributions of mushroom farming in the Global market. Thus, the popularity of mushroom farming and cultivation is increasing day ...after day. Weather monitoring and management is a significant feature for mushroom growth, especially the impact of temperature and humidity. Most of the farmers in remote areas worldwide use traditional ways to cultivate the mushrooms. The traditional way is very complicated, and often poisonous mushrooms appear due to the lack of sufficient weather and cultivation process monitoring. This paper reflects an architectural design of IoT & Machine Learning (ML)-based Smart Mushroom Farming. The proposed system introduces Remote Monitoring and Management (RMM), Farm Automation, and Mushroom classification. The Internet of Things (IoT), the microcontroller ESP32, and some agriculture-related sensors enable smart monitoring and farm automation. Machine Learning (ML) technology has been adopted to classify edible mushrooms to avoid poisonous mushrooms. To investigate the efficiency of the proposed system, several experiments have been enumerated and interpreted. The study is further furnished with the System Usability Scale (SUS) to track the regular user's satisfaction and gained the SUS score of 82%. The ML model is utilized by an ensemble model that is composed of six classifiers namely Decision Tree (DT), Logistic Regression (LR), K-nearest neighbor (KNN), Support Vector Machine (SVM), Naïve Bayes (NB), and Random Forest (RF). The highest accuracy gained with the ensemble model is 100% which outperforms each individual classifier. However, the system will be efficient for real-time farm automation and cultivation in the mushroom industry.
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Glutathione (GSH) was initially identified and characterized for its redox properties and later for its contributions to detoxification reactions. Over the past decade, however, the essential ...contributions of glutathione to cellular iron metabolism have come more and more into focus. GSH is indispensable in mitochondrial iron-sulfur (FeS) cluster biosynthesis, primarily by co-ligating FeS clusters as a cofactor of the CGFS-type (class II) glutaredoxins (Grxs). GSH is required for the export of the yet to be defined FeS precursor from the mitochondria to the cytosol. In the cytosol, it is an essential cofactor, again of the multi-domain CGFS-type Grxs, master players in cellular iron and FeS trafficking. In this review, we summarize the recent advances and progress in this field. The most urgent open questions are discussed, such as the role of GSH in the export of FeS precursors from mitochondria, the physiological roles of the CGFS-type Grx interactions with BolA-like proteins and the cluster transfer between Grxs and recipient proteins.
The spatio-temporal reduction and oxidation of protein thiols is an essential mechanism in signal transduction in all kingdoms of life. Thioredoxin (Trx) family proteins efficiently catalyze ...thiol-disulfide exchange reactions and the proteins are widely recognized for their importance in the operation of thiol switches. Trx family proteins have a broad and at the same time very distinct substrate specificity – a prerequisite for redox switching. Despite of multiple efforts, the true nature for this specificity is still under debate. Here, we comprehensively compare the classification/clustering of various redoxins from all domains of life based on their similarity in amino acid sequence, tertiary structure, and their electrostatic properties. We correlate these similarities to the existence of common interaction partners, identified in various previous studies and suggested by proteomic screenings. These analyses confirm that primary and tertiary structure similarity, and thereby all common classification systems, do not correlate to the target specificity of the proteins as thiol-disulfide oxidoreductases. Instead, a number of examples clearly demonstrate the importance of electrostatic similarity for their target specificity, independent of their belonging to the Trx or glutaredoxin subfamilies.
Mathematical biosciences; Biocomputational method; Biomolecules; Molecular docking; Gromov-Wasserstein distance; Protein-protein interaction; Redox signaling; Electrostatics; Thioredoxin; Glutaredoxin
The mammalian cytosolic thioredoxin (Trx) system consists of Trx1 and its reductase, the NADPH-dependent seleno-enzyme TrxR1. These proteins function as electron donor for metabolic enzymes, for ...instance in DNA synthesis, and the redox regulation of numerous processes. In this work, we analysed the interactions between these two proteins. We proposed electrostatic complementarity as major force controlling the formation of encounter complexes between the proteins and thus the efficiency of the subsequent electron transfer reaction. If our hypothesis is valid, formation of the encounter complex should be independent of the redox reaction. In fact, we were able to confirm that also a redox inactive mutant of Trx1 lacking both active site cysteinyl residues (C32,35S) binds to TrxR1 in a similar manner and with similar kinetics as the wild-type protein. We have generated a number of mutants with alterations in electrostatic properties and characterised their interaction with TrxR1 in kinetic assays. For human Trx1 and TrxR1, complementary electrostatic surfaces within the area covered in the encounter complex appear to control the affinity of the reductase for its substrate Trx. Electrostatic compatibility was even observed in areas that do not form direct molecular interactions in the encounter complex, and our results suggest that the electrostatic complementarity in these areas influences the catalytic efficiency of the reduction. The human genome encodes ten cytosolic Trx-like or Trx domain-containing proteins. In agreement with our hypothesis, the proteins that have been characterised as TrxR1 substrates also show the highest similarity in their electrostatic properties.
The prevalence of multidrug-resistant
is of global concern, and vaccines are urgently needed. The iron-regulated surface determinant protein B (IsdB) of
was investigated as a vaccine candidate ...because of its essential role in bacterial iron acquisition but failed in clinical trials despite strong immunogenicity. Here, we reveal an unexpected second function for IsdB in pathogen-host interaction: the bacterial fitness factor IsdB triggers a strong inflammatory response in innate immune cells via Toll-like receptor 4 and the inflammasome, thus acting as a novel pathogen-associated molecular pattern of
. Our discovery contributes to a better understanding of how
modulates the immune response, which is necessary for vaccine development against the sophisticated pathogen.
A cabinet type solar dryer was designed and fabricated over a collector and dryer area of 4.00 m2 and 7.5 m2 respectively for the geographical condition of Bangladesh. Red pepper was used to test the ...performance of the dryer. The upper tray and lower tray pepper drying needed 36 and 41 h to reduce moisture from 73% (wet basis) to 10% (wet basis) respectively and found 9 kg dried pepper from 30 kg fresh red ripe pepper. In contrast, open sun drying needed 85 h to reduce moisture from 73% (wet basis) to 11% (wet basis) and produced 2.43 kg dried pepper from 8 kg red ripe pepper. The average global radiation was about 133 W/m2 while the flux incidence and flux absorbed on collector was about 128 W/m2 and 103 W/m2 respectively. The average collector and dryer efficiency was about 48% and 34% respectively. The average exergy efficiency was obtained 63%. The average rate of top, bottom and side collector loss was 37 W/m2, 20 W/m2 and 3 W/m2 respectively. The upper tray, lower tray and open sun pepper seed germination was 76%, 81% and 85% respectively (P≥0.01). The redness value of lower tray pepper (a*=27.1) was higher followed by upper tray (a*=24.7) and open sun pepper powder (a*=21.1), which means direct exposure of sunlight diminishes the quality of pepper colour. The redness value of fabricated solar drying was significantly (P≤0.01) higher than that of open sun drying.
Abstract Reactive oxygen species (ROS) are important secondary messengers involved in a variety of cellular processes, including activation, proliferation, and differentiation. Hydrogen peroxide (H 2 ...O 2 ) is a major ROS typically kept in low nanomolar range that causes cell and tissue damage at supraphysiological concentrations. While ROS have been studied in detail at molecular scale, little is known about their impact on cell mechanical properties as label-free biomarker for stress response. Here, we exposed human myeloid precursor cells, T-lymphoid cells and neutrophils to varying concentrations of H 2 O 2 and show that elevated levels of mitochondrial superoxide are accompanied by an increased Young’s modulus. Mechanical alterations do not originate from global modifications in filamentous actin and microtubules but from cytosolic acidification due to lysosomal degradation. Finally, we demonstrate our findings to be independent of the presence of H 2 O 2 and that stiffening seems to be a general response of cells to stress factors lowering cytosolic pH.
Solanum sisymbriifolium (Solanaceae) and Jatropha gossypifolia (Euphorbiaceae) have long been used in folkloric medicine for the treatment of various ailments. The purpose of the present study was to ...evaluate the cytotoxic activity of the plants and to make available the process of data analysis of cytotoxic studies to the researchers. A general toxicity of the extracts was assessed by a simple and low cost assay using brine shrimp lethality as an indicator of toxicity. Ethanol crude extract and fractions of the extract of leaves of Solanum sisymbriifolium exhibited relatively mild cytotoxic activity compared to that of flowers and fruits against brine shrimp larvae with median lethal concentration, LC sub( 50) values ranging from 10.10 - 321.35 and 13.19 - 80.16 mu g/ml, respectively. Methanol crude extract and fractions of the extract of leaves of Jatropha gossypifolia exhibited significant toxicity against the shrimps (LC50 values 17.19 - 98.19 mu g/ml), while that of potassium permanganate, a positive control, was 11.27 mu g/ml. Among the fractions of the crude extracts of both plants, non-polar fractions such as n-hexane, chloroform, dichloromethane were the most cytotoxic. These results warrant follow-up through bioassay directed isolation of the active principles.
Abstract
This research article demonstrates a good simulation result for identifying and detecting various industrial chemicals in a Terahertz (THz) waveguide with a new heptagonal, five layers of ...heptagonal photonic fiber elliptic form, heptagonal cladding shape (H-PCF). COMSOL 4.2 software based on finite element (FEM) methods and perfectly matched layers check our composition (PML). The different chemicals are also differentiated and identified by each other in different parameters H-PCF fibers show a high relative sensitivity of ethanol of approximately 86.50 percent after numerical analysis, Benzene around 89.35%, and water around 85.15% at a frequency of around 0.7 THz. In our experiment, we obtained very low confinement losses at 1 terahertz (THz) such as 5.95 × 10
−08
dB/m for Ethanol 6.67 × 10
−08
dB/m for Benzene, and 5.80 × 10
−08
dB/m for water. Regarding these results, we can strongly recommend that our proposed heptagonal photonic crystal fiber (H-PCF) will be more congenial in biomedical, bio-medicine, and industrial areas for the identification and detection of various types of chemicals with the help of a THz waveguide.
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