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1.
Rev Assoc Med Bras (1992) ; 70(4): e20231120, 2024.
Article En | MEDLINE | ID: mdl-38716937

OBJECTIVE: We aimed to examine the effect of remission status on thiol-disulfide homeostasis in celiac patients and thus to indirectly determine the effect of oxidative stress and inflammation caused by non-compliance with the diet. METHODS: Between February 2019 and December 2021, 117 patients diagnosed with celiac disease were included in this prospective randomized and controlled study. In addition to routine tests of celiac patients, thiol and disulfide measurements were made from the blood both at the beginning of the study and at the end of the first year. RESULTS: While 52 of the patients (44.4%) were in remission, 65 patients (55.6%) were not. There was an evident increase in native thiol levels of the patients who were initially not in remission but went into at the end of the first year (347.4±46.7 µmol/L vs. 365.3±44.0 µmol/L; p=0.001). Mean plasma disulfide levels of patients with celiac going into remission became reduced in the first year from the level of 14.5±5.1 µmol/L down to 8.9±4.2 µmol/L (p<0.001). In celiac patients who entered remission, disulfide and anti-tissue transglutaminase immunoglobulin A levels decreased in a correlation (r=0.526; p<0.001). CONCLUSION: Not being in remission in celiac disease leads to increased oxidative stress, and thiol-disulfide homeostasis is an indirect indicator of this. Additionally, providing remission in celiac patients reduces oxidative stress.


Celiac Disease , Diet, Gluten-Free , Disulfides , Oxidative Stress , Patient Compliance , Sulfhydryl Compounds , Humans , Celiac Disease/diet therapy , Celiac Disease/blood , Oxidative Stress/physiology , Female , Male , Disulfides/blood , Prospective Studies , Sulfhydryl Compounds/blood , Adult , Remission Induction , Young Adult , Adolescent , Middle Aged , Immunoglobulin A/blood , Transglutaminases/blood
2.
Nat Commun ; 15(1): 3827, 2024 May 07.
Article En | MEDLINE | ID: mdl-38714735

The main protease (Mpro) of SARS-CoV-2 is critical for viral function and a key drug target. Mpro is only active when reduced; turnover ceases upon oxidation but is restored by re-reduction. This suggests the system has evolved to survive periods in an oxidative environment, but the mechanism of this protection has not been confirmed. Here, we report a crystal structure of oxidized Mpro showing a disulfide bond between the active site cysteine, C145, and a distal cysteine, C117. Previous work proposed this disulfide provides the mechanism of protection from irreversible oxidation. Mpro forms an obligate homodimer, and the C117-C145 structure shows disruption of interactions bridging the dimer interface, implying a correlation between oxidation and dimerization. We confirm dimer stability is weakened in solution upon oxidation. Finally, we observe the protein's crystallization behavior is linked to its redox state. Oxidized Mpro spontaneously forms a distinct, more loosely packed lattice. Seeding with crystals of this lattice yields a structure with an oxidation pattern incorporating one cysteine-lysine-cysteine (SONOS) and two lysine-cysteine (NOS) bridges. These structures further our understanding of the oxidative regulation of Mpro and the crystallization conditions necessary to study this structurally.


Catalytic Domain , Coronavirus 3C Proteases , Cysteine , Disulfides , Oxidation-Reduction , SARS-CoV-2 , Disulfides/chemistry , Disulfides/metabolism , SARS-CoV-2/metabolism , SARS-CoV-2/chemistry , Coronavirus 3C Proteases/metabolism , Coronavirus 3C Proteases/chemistry , Cysteine/chemistry , Cysteine/metabolism , Crystallography, X-Ray , Humans , Models, Molecular , Protein Multimerization , COVID-19/virology
3.
Brief Bioinform ; 25(3)2024 Mar 27.
Article En | MEDLINE | ID: mdl-38706323

In recent years, cyclic peptides have emerged as a promising therapeutic modality due to their diverse biological activities. Understanding the structures of these cyclic peptides and their complexes is crucial for unlocking invaluable insights about protein target-cyclic peptide interaction, which can facilitate the development of novel-related drugs. However, conducting experimental observations is time-consuming and expensive. Computer-aided drug design methods are not practical enough in real-world applications. To tackles this challenge, we introduce HighFold, an AlphaFold-derived model in this study. By integrating specific details about the head-to-tail circle and disulfide bridge structures, the HighFold model can accurately predict the structures of cyclic peptides and their complexes. Our model demonstrates superior predictive performance compared to other existing approaches, representing a significant advancement in structure-activity research. The HighFold model is openly accessible at https://github.com/hongliangduan/HighFold.


Disulfides , Peptides, Cyclic , Peptides, Cyclic/chemistry , Disulfides/chemistry , Software , Models, Molecular , Protein Conformation , Algorithms , Computational Biology/methods
4.
Bioresour Technol ; 401: 130761, 2024 Jun.
Article En | MEDLINE | ID: mdl-38692370

Cr (VI) is a common heavy metal pollutant in electroplating wastewater. This study introduces the liquid-phase product from the hydrothermal reaction of coffee grounds (CGHCL) into the synthesis process of molybdenum disulfide, assisting in the fabrication of an intercalated, expanded core-shell structured molybdenum disulfide adsorbent (C-MoS2), designed for the adsorption and reduction of Cr (VI) from electroplating wastewater. The addition of CGHCL significantly enhances the adsorption performance of MoS2. Furthermore, C-MoS2 exhibits exceedingly high removal efficiency and excellent regenerative capability for Cr (VI)-containing electroplating wastewater. The core-shell structure effectively minimizes molybdenum leaching to the greatest extent, while the oleophobic interface is unaffected by oily substances in water, and the expanded interlayer structure ensures the long-term stability of C-MoS2 in air (90 days). This study provides a viable pathway for the resource utilization of biomass and the application of molybdenum disulfide-based materials in wastewater treatment.


Biomass , Chromium , Disulfides , Molybdenum , Wastewater , Water Purification , Molybdenum/chemistry , Disulfides/chemistry , Adsorption , Wastewater/chemistry , Water Purification/methods , Chromium/chemistry , Electroplating , Water Pollutants, Chemical , Solutions
5.
Colloids Surf B Biointerfaces ; 238: 113885, 2024 Jun.
Article En | MEDLINE | ID: mdl-38574405

We demonstrate light-triggered dynamic covalent assembly of a linear short tetrapeptide containing two terminal cysteine residues in an AND logic manner. A photobase generator is introduced to accomplish light-mediated pH regulation to increase the reduction potential of thiols in the tetrapeptide, which activates its oxidative polymerization through disulfide bonds. Interestingly, it is elucidated that under light irradiation, mere co-existence of photobase generator and the oxidizing agent permits the polymerization performance of this tetrapeptide. Hence, a light-triggered AND logic dynamic covalent assembly of a tetrapeptide is achieved. Further, upon redox response, the reversible aggregation and disaggregation can be transformed for numerous times due to the dynamic covalent feature of disulfide bond. As a comparison, no assembly occurs for a short peptide containing one terminal cysteine residue under the same stimuli condition. This work offers a new approach to remotely control programmable molecular assembly of short linear peptides based on dynamic covalent bond, holding great potential in wide bioapplications.


Light , Hydrogen-Ion Concentration , Oligopeptides/chemistry , Oxidation-Reduction , Polymerization , Cysteine/chemistry , Disulfides/chemistry , Sulfhydryl Compounds/chemistry , Logic
6.
Chemosphere ; 357: 142033, 2024 Jun.
Article En | MEDLINE | ID: mdl-38615961

The design and preparation of dual-functional photocatalysts for simultaneously realizing photocatalytic wastewater purification and hydrogen energy generation pose significant challenges. This article presents the engineering of a binary heterostructured photocatalyst by combining TiO2 (nanorods) and MoS2 nanosphere using a straightforward solvothermal method and the assessment of the phase structures, morphologies, and optical properties of the resulting nanocomposites using diverse analytical techniques. The TiO2(Rod)/MoS2 composite exhibits remarkable efficacy in degrading ciprofloxacin, achieving 93% removal rate within 1 h, which is four times higher than that of bare TiO2. Moreover, the optimized TiO2(Rod)/MoS2 presents an outstanding hydrogen production rate of 7415 µmol g-1, which is ∼24 times higher than that of pristine TiO2. Under UV-visible light irradiation, the TiO2(Rod)/MoS2 heterojunction displays an exceptional photocatalytic performance in terms of both photodegradation and hydrogen production, surpassing the performance of TiO2 particle/MoS2. The study findings demonstrate that TiO2(Rod)/MoS2 nanocomposites exhibit considerably improved photocatalytic degradation and hydrogen generation activities. Based on the experimental results, a possible mechanism is proposed for the transfer and separation of charge carriers in Z-scheme heterojunctions.


Anti-Bacterial Agents , Disulfides , Hydrogen , Molybdenum , Nanospheres , Nanotubes , Titanium , Titanium/chemistry , Molybdenum/chemistry , Catalysis , Anti-Bacterial Agents/chemistry , Nanospheres/chemistry , Hydrogen/chemistry , Disulfides/chemistry , Nanotubes/chemistry , Nanocomposites/chemistry , Photolysis , Water Pollutants, Chemical/chemistry , Wastewater/chemistry , Ciprofloxacin/chemistry
7.
J Mater Chem B ; 12(19): 4724-4735, 2024 May 15.
Article En | MEDLINE | ID: mdl-38655674

We have developed a highly sensitive and reliable fluorescence resonance energy transfer (FRET) probe using nitro-dopamine (ND) and dopamine (DA) coated MnO2 nanosheet (ND@MnO2 NS and DA@MnO2 NS) as an energy acceptor and MoS2 quantum dots (QDs) as an energy donor. By employing surface-modified MnO2 NS, we can effectively reduce the fluorescence intensity of MoS2 QDs through FRET. It can reduce MnO2 NS to Mn2+ and facilitate the fluorescence recovery of the MoS2 QDs. This ND@MnO2 NS@MoS2 QD-based nanoprobe demonstrates excellent sensitivity to GSH, achieving an LOD of 22.7 nM in an aqueous medium while exhibiting minimal cytotoxicity and good biocompatibility. Moreover, our sensing platform shows high selectivity to GSH towards various common biomolecules and electrolytes. Confocal fluorescence imaging revealed that the nanoprobe can image GSH in A549 cells. Interestingly, the ND@MnO2 NS nanoprobe demonstrates no cytotoxicity in living cancer cells, even at concentrations up to 100 µg mL-1. Moreover, the easy fabrication and eco-friendliness of ND@MnO2 NS make it a rapid and simple method for detecting GSH. We envision the developed nanoprobe as an incredible platform for real-time monitoring of GSH levels in both extracellular and intracellular mediums, proving valuable for biomedical research and clinical diagnostics.


Disulfides , Dopamine , Glutathione , Manganese Compounds , Molybdenum , Nanocomposites , Oxides , Quantum Dots , Humans , Manganese Compounds/chemistry , Disulfides/chemistry , Oxides/chemistry , Quantum Dots/chemistry , Molybdenum/chemistry , Glutathione/analysis , Glutathione/chemistry , Dopamine/analysis , Nanocomposites/chemistry , Fluorescence Resonance Energy Transfer , A549 Cells , Particle Size , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis
8.
Int J Mol Sci ; 25(7)2024 Apr 01.
Article En | MEDLINE | ID: mdl-38612753

Refolding multi-disulfide bonded proteins expressed in E. coli into their native structure is challenging. Nevertheless, because of its cost-effectiveness, handiness, and versatility, the E. coli expression of viral envelope proteins, such as the RBD (Receptor-Binding Domain) of the influenza Hemagglutinin protein, could significantly advance research on viral infections. Here, we show that H1N1-PR8-RBD (27 kDa, containing four cysteines forming two disulfide bonds) expressed in E. coli and was purified with nickel affinity chromatography, and reversed-phase HPLC was successfully refolded into its native structure, as assessed with several biophysical and biochemical techniques. Analytical ultracentrifugation indicated that H1N1-PR8-RBD was monomeric with a hydrodynamic radius of 2.5 nm. Thermal denaturation, monitored with DSC and CD at a wavelength of 222 nm, was cooperative with a midpoint temperature around 55 °C, strongly indicating a natively folded protein. In addition, the 15N-HSQC NMR spectrum exhibited several 1H-15N resonances indicative of a beta-sheeted protein. Our results indicate that a significant amount (40 mg/L) of pure and native H1N1-PR8-RBD can be produced using an E. coli expression system with our refolding procedure, offering potential insights into the molecular characterization of influenza virus infection.


Influenza A Virus, H1N1 Subtype , Influenza, Human , Orthomyxoviridae Infections , Humans , Escherichia coli/genetics , Disulfides
9.
J Chromatogr A ; 1722: 464828, 2024 May 10.
Article En | MEDLINE | ID: mdl-38581973

The linkages of disulfide bond (DSB) play important roles in protein stability and activity. Mass spectrometry-based (MS-based) techniques become accepted tools for DSB analysis in the recent decade. In the bottom-up approach, after enzyme digestion, the neighbouring amino acids of cysteines have great impacts on the physicochemical properties of resulting disulfide bond peptides, determining their retention behaviour on liquid chromatography (LC) and their MS ionization efficiency. In this study, the addition of supercharging reagent in LC mobile phase was used to examine the impact of supercharging reagent on the charge states of disulfide-bond peptides. The results showed that 0.1 % m-nitrobenzyl alcohol (m-NBA) in LC mobile phase increased the sensitivity and charge states of DSB peptides from our model protein, equine Interleukin-5 (eIL5), as well as the resolution of reversed-phase chromatography. Notably, also the sensitivity of C-terminal peptide with His-tag significantly improved. Our findings highlight the effectiveness of employing m-NBA as a supercharging reagent when investigating disulfide-linked peptides and the C-terminal peptide with a His-tag through nano-liquid chromatography mass spectrometry.


Benzyl Alcohols , Disulfides , Peptides , Disulfides/chemistry , Benzyl Alcohols/chemistry , Benzyl Alcohols/isolation & purification , Peptides/chemistry , Peptides/isolation & purification , Animals , Horses , Histidine/chemistry , Chromatography, Liquid/methods , Chromatography, Reverse-Phase/methods , Chromatography, High Pressure Liquid/methods
10.
Commun Biol ; 7(1): 501, 2024 Apr 25.
Article En | MEDLINE | ID: mdl-38664468

G protein-coupled receptors naturally oscillate between inactive and active states, often resulting in receptor constitutive activity with important physiological consequences. Among the class C G protein-coupled receptors that typically sense amino-acids and their derivatives, the calcium sensing receptor (CaSR) tightly controls blood calcium levels. Its constitutive activity has not yet been studied. Here, we demonstrate the importance of the inter-subunit disulfide bridges in maintaining the inactive state of CaSR, resulting in undetectable constitutive activity, unlike the other class C receptors. Deletion of these disulfide bridges results in strong constitutive activity that is abolished by mutations preventing amino acid binding. It shows that this inter-subunit disulfide link is necessary to limit the agonist effect of amino acids on CaSR. Furthermore, human genetic mutations deleting these bridges and associated with hypocalcemia result in elevated CaSR constitutive activity. These results highlight the physiological importance of fine tuning the constitutive activity of G protein-coupled receptors.


Disulfides , Receptors, Calcium-Sensing , Receptors, Calcium-Sensing/metabolism , Receptors, Calcium-Sensing/genetics , Humans , Disulfides/metabolism , Disulfides/chemistry , HEK293 Cells , Calcium/metabolism , Mutation , Animals
11.
Bioorg Med Chem Lett ; 104: 129729, 2024 May 15.
Article En | MEDLINE | ID: mdl-38583786

Aptamers have shown significant potential in treating diverse diseases. However, challenges such as stability and drug delivery limited their clinical application. In this paper, the development of AS1411 prodrug-type aptamers for tumor treatment was introduced. A Short oligonucleotide was introduced at the end of the AS1411 sequence with a disulfide bond as responsive switch. The results indicated that the aptamer prodrugs not only enhanced the stability of the aptamer against nuclease activity but also facilitated binding to serum albumin. Furthermore, in the reducing microenvironment of tumor cells, disulfide bonds triggered drug release, resulting in superior therapeutic effects in vitro and in vivo compared to original drugs. This paper proposes a novel approach for optimizing the structure of nucleic acid drugs, that promises to protect other oligonucleotides or secondary structures, thus opening up new possibilities for nucleic acid drug design.


Aptamers, Nucleotide , Nucleic Acids , Prodrugs , Prodrugs/chemistry , Drug Delivery Systems , Aptamers, Nucleotide/pharmacology , Disulfides/chemistry , Cell Line, Tumor
12.
Eur Rev Med Pharmacol Sci ; 28(7): 2817-2826, 2024 Apr.
Article En | MEDLINE | ID: mdl-38639521

OBJECTIVE: Testicular ischemia-reperfusion induced by testicular torsion-detorsion increases the level of reactive oxygen species, leading to testicular damage. Allicin, one of the most active ingredients in garlic, is a significant exogenous antioxidant. In the research, the efficacy of allicin in treating testicular ischemia-reperfusion injury was assessed. MATERIALS AND METHODS: The study included sixty Sprague-Dawley male rats. Three groups with 20 rats per group were created as follows: control group, testicular ischemia/reperfusion-induced group, and testicular ischemia-reperfusion plus treatment with allicin group. The control group underwent a sham operation of the left testis without other interventions. In the testicular ischemia/reperfusion-induced group, rat left testis was subjected to 720° torsion for two hours and then detorsion. In the allicin-treated group, in addition to testicular ischemia-reperfusion, 50 mg/kg of allicin was injected intraperitoneally, starting immediately following detorsion. Testicular tissue samples were obtained to measure the protein expression of xanthine oxidase, which is a major source of reactive oxygen species formation, malondialdehyde level (a reliable marker of reactive oxygen species), and testicular spermatogenic function. RESULTS: Testicular ischemia-reperfusion significantly increased the expression of xanthine oxidase and malondialdehyde levels in ipsilateral testes while reducing testicular spermatogenic function. The expression of xanthine oxidase and malondialdehyde levels were significantly lower in ipsilateral testes, whereas testicular spermatogenic function in the allicin-treated group was significantly higher compared with those in the testicular ischemia-reperfusion group. CONCLUSIONS: Our findings indicate that allicin administration improves ischemia/reperfusion-induced testicular damage by limiting reactive oxygen species generation via inhibition of xanthine oxidase expression.


Disulfides , Reperfusion Injury , Spermatic Cord Torsion , Sulfinic Acids , Rats , Male , Animals , Humans , Spermatic Cord Torsion/drug therapy , Spermatic Cord Torsion/complications , Spermatic Cord Torsion/metabolism , Rats, Sprague-Dawley , Xanthine Oxidase/metabolism , Xanthine Oxidase/pharmacology , Reactive Oxygen Species/metabolism , Testis , Reperfusion Injury/metabolism , Antioxidants/pharmacology , Ischemia/metabolism , Malondialdehyde/metabolism
13.
Plant Cell Rep ; 43(4): 108, 2024 Apr 01.
Article En | MEDLINE | ID: mdl-38557872

KEY MESSAGE: The CcGRXS12 gene protects plants from cellular oxidative damage that are caused by both biotic and abiotic stresses. The protein possesses GSH-disulphide oxidoreductase property but lacks Fe-S cluster assembly mechanism. Glutaredoxins (Grxs) are small, ubiquitous and multi-functional proteins. They are present in different compartments of plant cells. A chloroplast targeted Class I GRX (CcGRXS12) gene was isolated from Capsicum chinense during the pepper mild mottle virus (PMMoV) infection. Functional characterization of the gene was performed in Nicotiana benthamiana transgenic plants transformed with native C. chinense GRX (Nb:GRX), GRX-fused with GFP (Nb:GRX-GFP) and GRX-truncated for chloroplast sequences fused with GFP (Nb:Δ2MGRX-GFP). Overexpression of CcGRXS12 inhibited the PMMoV-I accumulation at the later stage of infection, accompanied with the activation of salicylic acid (SA) pathway pathogenesis-related (PR) transcripts and suppression of JA/ET pathway transcripts. Further, the reduced accumulation of auxin-induced Glutathione-S-Transferase (pCNT103) in CcGRXS12 overexpressing lines indicated that the protein could protect the plants from the oxidative stress caused by the virus. PMMoV-I infection increased the accumulation of pyridine nucleotides (PNs) mainly due to the reduced form of PNs (NAD(P)H), and it was high in Nb:GRX-GFP lines compared to other transgenic lines. Apart from biotic stress, CcGRXS12 protects the plants from abiotic stress conditions caused by H2O2 and herbicide paraquat. CcGRXS12 exhibited GSH-disulphide oxidoreductase activity in vitro; however, it was devoid of complementary Fe-S cluster assembly mechanism found in yeast. Overall, this study proves that CcGRXS12 plays a crucial role during biotic and abiotic stress in plants.


Capsicum , Tobamovirus , Capsicum/genetics , Capsicum/metabolism , Glutaredoxins/genetics , Glutaredoxins/metabolism , Hydrogen Peroxide , Oxidation-Reduction , Disulfides
14.
Top Curr Chem (Cham) ; 382(2): 13, 2024 Apr 12.
Article En | MEDLINE | ID: mdl-38607428

The synthesis of thioether derivatives has been explored widely due to the potential application of these derivatives in medicinal chemistry, pharmaceutical industry and material chemistry. Within this context, there has been an increasing demand for the environmentally benign construction of C-S bonds via C-H functionalization under metal-free conditions. In the present article, we highlight recent developments in metal-free sulfenylation that have occurred in the past three years. The synthesis of organosulfur compounds via a metal-free approach using a variety of sulfur sources, including thiophenols, disulfides, sulfonyl hydrazides, sulfonyl chlorides, elemental sulfur and sulfinates, is discussed. Non-conventional strategies, which refer to the development of thioether derivatives under visible light and electrochemically mediated conditions, are also discussed. The key advantages of the reviewed methodologies include broad substrate scope and high reaction yields under environmentally benign conditions. This comprehensive review will provide chemists with a synthetic tool that will facilitate further development in this field.


Disulfides , Hydrazines , Light , Metals , Sulfur
15.
J Nanobiotechnology ; 22(1): 147, 2024 Apr 03.
Article En | MEDLINE | ID: mdl-38570829

The challenges associated with activating ferroptosis for cancer therapy primarily arise from obstacles related to redox and iron homeostasis, which hinder the susceptibility of tumor cells to ferroptosis. However, the specific mechanisms of ferroptosis resistance, especially those intertwined with abnormal metabolic processes within tumor cells, have been consistently underestimated. In response, we present an innovative glutathione-responsive magnetocaloric therapy nanodrug termed LFMP. LFMP consists of lonidamine (LND) loaded into PEG-modified magnetic nanoparticles with a Fe3O4 core and coated with disulfide bonds-bridged mesoporous silica shells. This nanodrug is designed to induce an accelerated ferroptosis-activating state in tumor cells by disrupting homeostasis. Under the dual effects of alternating magnetic fields and high concentrations of glutathione in the tumor microenvironment, LFMP undergoes disintegration, releasing drugs. LND intervenes in cell metabolism by inhibiting glycolysis, ultimately enhancing iron death and leading to synthetic glutathione consumption. The disulfide bonds play a pivotal role in disrupting intracellular redox homeostasis by depleting glutathione and inactivating glutathione peroxidase 4 (GPX4), synergizing with LND to enhance the sensitivity of tumor cells to ferroptosis. This process intensifies oxidative stress, further impairing redox homeostasis. Furthermore, LFMP exacerbates mitochondrial dysfunction, triggering ROS formation and lactate buildup in cancer cells, resulting in increased acidity and subsequent tumor cell death. Importantly, LFMP significantly suppresses tumor cell proliferation with minimal side effects both in vitro and in vivo, exhibiting satisfactory T2-weighted MR imaging properties. In conclusion, this magnetic hyperthermia-based nanomedicine strategy presents a promising and innovative approach for antitumor therapy.


Ferroptosis , Neoplasms , Humans , Glutathione , Iron , Lactic Acid , Glucose , Disulfides , Neoplasms/drug therapy , Cell Line, Tumor , Reactive Oxygen Species , Tumor Microenvironment
16.
BMC Plant Biol ; 24(1): 229, 2024 Apr 01.
Article En | MEDLINE | ID: mdl-38561653

BACKGROUND: BAHD acyltransferases are among the largest metabolic protein domain families in the genomes of terrestrial plants and play important roles in plant growth and development, aroma formation, and biotic and abiotic stress responses. Little is known about the BAHDs in the tea plant, a cash crop rich in secondary metabolites. RESULTS: In this study, 112 BAHD genes (CsBAHD01-CsBAHD112) were identified from the tea plant genome, with 85% (98/112) unevenly distributed across the 15 chromosomes. The number of BAHD gene family members has significantly expanded from wild tea plants to the assamica type to the sinensis type. Phylogenetic analysis showed that they could be classified into seven subgroups. Promoter cis-acting element analysis revealed that they contain a large number of light, phytohormones, and stress-responsive elements. Many members displayed tissue-specific expression patterns. CsBAHD05 was expressed at more than 500-fold higher levels in purple tea leaves than in green tea leaves. The genes exhibiting the most significant response to MeJA treatment and feeding by herbivorous pests were primarily concentrated in subgroups 5 and 6. The expression of 23 members of these two subgroups at different time points after feeding by tea green leafhoppers and tea geometrids was examined via qPCR, and the results revealed that the expression of CsBAHD93, CsBAHD94 and CsBAHD95 was significantly induced after the tea plants were subjected to feeding by both pricking and chewing pests. Moreover, based on the transcriptome data for tea plants being fed on by these two pests, a transcriptional regulatory network of different transcription factor genes coexpressed with these 23 members was constructed. CONCLUSIONS: Our study provides new insights into the role of BAHDs in the defense response of tea plants, and will facilitate in-depth studies of the molecular function of BAHDs in resistance to herbivorous pests.


Amines , Camellia sinensis , Disulfides , Camellia sinensis/metabolism , Phylogeny , Genome, Plant , Tea/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Gene Expression Regulation, Plant
17.
Int J Mol Sci ; 25(8)2024 Apr 09.
Article En | MEDLINE | ID: mdl-38673722

The human Vitamin K Epoxide Reductase Complex (hVKORC1), a key enzyme that converts vitamin K into the form necessary for blood clotting, requires for its activation the reducing equivalents supplied by its redox partner through thiol-disulphide exchange reactions. The functionally related molecular complexes assembled during this process have never been described, except for a proposed de novo model of a 'precursor' complex of hVKORC1 associated with protein disulphide isomerase (PDI). Using numerical approaches (in silico modelling and molecular dynamics simulation), we generated alternative 3D models for each molecular complex bonded either covalently or non-covalently. These models differ in the orientation of the PDI relative to hVKORC1 and in the cysteine residue involved in forming protein-protein disulphide bonds. Based on a comparative analysis of these models' shape, folding, and conformational dynamics, the most probable putative complexes, mimicking the 'precursor', 'intermediate', and 'successor' states, were suggested. In addition, we propose using these complexes to develop the 'allo-network drugs' necessary for treating blood diseases.


Molecular Dynamics Simulation , Protein Disulfide-Isomerases , Vitamin K Epoxide Reductases , Protein Disulfide-Isomerases/metabolism , Protein Disulfide-Isomerases/chemistry , Vitamin K Epoxide Reductases/chemistry , Vitamin K Epoxide Reductases/metabolism , Vitamin K Epoxide Reductases/genetics , Humans , Disulfides/chemistry , Disulfides/metabolism , Sulfhydryl Compounds/chemistry , Sulfhydryl Compounds/metabolism , Models, Molecular , Protein Conformation , Oxidation-Reduction , Protein Binding
18.
J Integr Neurosci ; 23(4): 85, 2024 Apr 22.
Article En | MEDLINE | ID: mdl-38682214

BACKGROUND: Alzheimer's disease (AD) is a condition that affects the nervous system and that requires considerably more in-depth study. Abnormal Nicotinamide Adenine Dinucleotide (NAD+) metabolism and disulfide levels have been demonstrated in AD. This study investigated novel hub genes for disulfide levels and NAD+ metabolism in relation to the diagnosis and therapy of AD. METHODS: Data from the gene expression omnibus (GEO) database were analyzed. Hub genes related to disulfide levels, NAD+ metabolism, and AD were identified from overlapping genes for differentially expressed genes (DEGs), genes in the NAD+ metabolism or disulfide gene sets, and module genes obtained by weighted gene co-expression network analysis (WGCNA). Pathway analysis of these hub genes was performed by Gene Set Enrichment Analysis (GSEA). A diagnostic model for AD was constructed based on the expression level of hub genes in brain samples. CIBERSORT was used to evaluate immune cell infiltration and immune factors correlating with hub gene expression. The DrugBank database was also used to identify drugs that target the hub genes. RESULTS: We identified 3 hub genes related to disulfide levels in AD and 9 related to NAD+ metabolism in AD. Pathway analysis indicated these 12 genes were correlated with AD. Stepwise regression analysis revealed the area under the curve (AUC) for the predictive model based on the expression of these 12 hub genes in brain tissue was 0.935, indicating good diagnostic performance. Additionally, analysis of immune cell infiltration showed the hub genes played an important role in AD immunity. Finally, 33 drugs targeting 10 hub genes were identified using the DrugBank database. Some of these have been clinically approved and may be useful for AD therapy. CONCLUSION: Hub genes related to disulfide levels and NAD+ metabolism are promising biomarkers for the diagnosis of AD. These genes may contribute to a better understanding of the pathogenesis of AD, as well as to improved drug therapy.


Alzheimer Disease , Disulfides , NAD , Alzheimer Disease/metabolism , Humans , NAD/metabolism , Disulfides/metabolism , Gene Regulatory Networks , Databases, Genetic
19.
Nat Commun ; 15(1): 3129, 2024 Apr 11.
Article En | MEDLINE | ID: mdl-38605050

The essence of difference between hemostasis and thrombosis is that the clotting reaction is a highly fine-tuned process. Vascular protein disulfide isomerase (PDI) represents a critical mechanism regulating the functions of hemostatic proteins. Herein we show that histidine-rich glycoprotein (HRG) is a substrate of PDI. Reduction of HRG by PDI enhances the procoagulant and anticoagulant activities of HRG by neutralization of endothelial heparan sulfate (HS) and inhibition of factor XII (FXIIa) activity, respectively. Murine HRG deficiency (Hrg-/-) leads to delayed onset but enhanced formation of thrombus compared to WT. However, in the combined FXII deficiency (F12-/-) and HRG deficiency (by siRNA or Hrg-/-), there is further thrombosis reduction compared to F12-/- alone, confirming HRG's procoagulant activity independent of FXIIa. Mutation of target disulfides of PDI leads to a gain-of-function mutant of HRG that promotes its activities during coagulation. Thus, PDI-HRG pathway fine-tunes thrombosis by promoting its rapid initiation via neutralization of HS and preventing excessive propagation via inhibition of FXIIa.


Protein Disulfide-Isomerases , Proteins , Thrombosis , Animals , Mice , Disulfides , Factor XII/metabolism , Heparitin Sulfate , Protein Disulfide-Isomerases/genetics , Proteins/metabolism , Thrombosis/genetics , Thrombosis/metabolism
20.
Sheng Wu Gong Cheng Xue Bao ; 40(4): 1076-1088, 2024 Apr 25.
Article Zh | MEDLINE | ID: mdl-38658150

Flavin-containing monooxygenase (FMO) is the key enzyme in the biosynthesis pathway of CSOs with sulfur oxidation. In order to explore the molecular regulatory mechanism of FMO in the synthesis of onion CSOs, based on transcriptome database and phylogenetic analysis, one AcFMO gene that may be involved in alliin synthesis was obtained, the AcFMO had a cDNA of 1 374 bp and encoded 457 amino acids, which was evolutionarily closest to the AsFMO of garlic. Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) indicated that AcFMO was the highest in the flowers and the lowest in the leaf sheaths. The results of subcellular localization showed that the AcFMO gene product was widely distributed throughout the cell A yeast expression vector was constructed, and the AcFMO gene was ecotopically overexpressed in yeast to further study the enzyme function in vitro and could catalyze the synthesis of alliin by S-allyl-l-cysteine. In summary, the cloning and functional identification of AcFMO have important reference value for understanding the biosynthesis of CSOs in onions.


Cloning, Molecular , Cysteine/analogs & derivatives , Onions , Onions/genetics , Onions/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Cysteine/biosynthesis , Cysteine/metabolism , Oxygenases/genetics , Oxygenases/metabolism , Amino Acid Sequence , Phylogeny , Disulfides/metabolism , Molecular Sequence Data , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism
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