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1.
Carbohydr Polym ; 339: 122251, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823918

RESUMO

In this study, the disulfide-linked hyaluronic acid (HA) hydrogels were optimised for potential application as a scaffold in tissue engineering through the Quality by Design (QbD) approach. For this purpose, HA was first modified by incorporating the cysteine moiety into the HA backbone, which promoted the formation of disulfide cross-linked HA hydrogel at physiological pH. Utilising a Design of Experiments (DoE) methodology, the critical factors to achieve stable biomaterials, i.e. the degree of HA substitution, HA molecular weight, and coupling agent ratio, were explored. To establish a design space, the DoE was performed with 65 kDa, 138 kDa and 200 kDa HA and variable concentrations of coupling agent to optimise conditions to obtain HA hydrogel with improved rheological properties. Thus, HA hydrogel with a 12 % degree of modification, storage modulus of ≈2321 Pa and loss modulus of ≈15 Pa, was achieved with the optimum ratio of coupling agent. Furthermore, biocompatibility assessments in C28/I2 chondrocyte cells demonstrated the non-toxic nature of the hydrogel, underscoring its potential for tissue regeneration. Our findings highlight the efficacy of the QbD approach in designing HA hydrogels with tailored properties for biomedical applications.


Assuntos
Materiais Biocompatíveis , Condrócitos , Dissulfetos , Ácido Hialurônico , Hidrogéis , Reologia , Engenharia Tecidual , Ácido Hialurônico/química , Hidrogéis/química , Hidrogéis/síntese química , Dissulfetos/química , Condrócitos/efeitos dos fármacos , Condrócitos/citologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio
2.
Microb Cell Fact ; 23(1): 166, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840157

RESUMO

BACKGROUND: Recombinant peptide production in Escherichia coli provides a sustainable alternative to environmentally harmful and size-limited chemical synthesis. However, in-vivo production of disulfide-bonded peptides at high yields remains challenging, due to degradation by host proteases/peptidases and the necessity of translocation into the periplasmic space for disulfide bond formation. RESULTS: In this study, we established an expression system for efficient and soluble production of disulfide-bonded peptides in the periplasm of E. coli. We chose model peptides with varying complexity (size, structure, number of disulfide bonds), namely parathyroid hormone 1-84, somatostatin 1-28, plectasin, and bovine pancreatic trypsin inhibitor (aprotinin). All peptides were expressed without and with the N-terminal, low molecular weight CASPON™ tag (4.1 kDa), with the expression cassette being integrated into the host genome. During BioLector™ cultivations at microliter scale, we found that most of our model peptides can only be sufficiently expressed in combination with the CASPON™ tag, otherwise expression was only weak or undetectable on SDS-PAGE. Undesired degradation by host proteases/peptidases was evident even with the CASPON™ tag. Therefore, we investigated whether degradation happened before or after translocation by expressing the peptides in combination with either a co- or post-translational signal sequence. Our results suggest that degradation predominantly happened after the translocation, as degradation fragments appeared to be identical independent of the signal sequence, and expression was not enhanced with the co-translational signal sequence. Lastly, we expressed all CASPON™-tagged peptides in two industry-relevant host strains during C-limited fed-batch cultivations in bioreactors. We found that the process performance was highly dependent on the peptide-host-combination. The titers that were reached varied between 0.6-2.6 g L-1, and exceeded previously published data in E. coli. Moreover, all peptides were shown by mass spectrometry to be expressed to completion, including full formation of disulfide bonds. CONCLUSION: In this work, we demonstrated the potential of the CASPON™ technology as a highly efficient platform for the production of soluble peptides in the periplasm of E. coli. The titers we show here are unprecedented whenever parathyroid hormone, somatostatin, plectasin or bovine pancreatic trypsin inhibitor were produced in E. coli, thus making our proposed upstream platform favorable over previously published approaches and chemical synthesis.


Assuntos
Dissulfetos , Escherichia coli , Peptídeos , Periplasma , Escherichia coli/metabolismo , Escherichia coli/genética , Periplasma/metabolismo , Dissulfetos/metabolismo , Peptídeos/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Aprotinina/metabolismo , Aprotinina/genética
3.
BMC Vet Res ; 20(1): 243, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38835040

RESUMO

BACKGROUND: The liver-expressed antimicrobial peptide 2 (LEAP2) plays a pivotal role in the host's immune response against pathogenic microorganisms. Numerous such antimicrobial peptides have recently been shown to mitigate infection risk in fish, and studying those harboured by the economically important fish Acrossocheilus fasciatus is imperative for enhancing its immune responses against pathogenic microorganisms. In this study, we cloned and sequenced LEAP2 cDNA from A. fasciatus to examine its expression in immune tissues and investigate the structure-activity relationships of its intramolecular disulphide bonds. RESULTS: The predicted amino acid sequence of A. fasciatus LEAP2 was found to include a signal peptide, pro-domain, and mature peptide. Sequence analysis indicated that A. fasciatus LEAP2 is a member of the fish LEAP2A cluster and is closely related to Cyprinus carpio LEAP2A. A. fasciatus LEAP2 transcripts were expressed in various tissues, with the head kidney exhibiting the highest mRNA levels. Upon exposure to Aeromonas hydrophila infection, LEAP2 expression was significantly upregulated in the liver, head kidney, and spleen. A mature peptide of A. fasciatus LEAP2, consisting of two disulphide bonds (Af-LEAP2-cys), and a linear form of the LEAP2 mature peptide (Af-LEAP2) were chemically synthesised. The circular dichroism spectroscopy result shows differences between the secondary structures of Af-LEAP2 and Af-LEAP2-cys, with a lower proportion of alpha helix and a higher proportion of random coil in Af-LEAP2. Af-LEAP2 exhibited potent antimicrobial activity against most tested bacteria, including Acinetobacter guillouiae, Pseudomonas aeruginosa, Staphylococcus saprophyticus, and Staphylococcus warneri. In contrast, Af-LEAP2-cys demonstrated weak or no antibacterial activity against the tested bacteria. Af-LEAP2 had a disruptive effect on bacterial cell membrane integrity, whereas Af-LEAP2-cys did not exhibit this effect. Additionally, neither Af-LEAP2 nor Af-LEAP2-cys displayed any observable ability to hydrolyse the genomic DNA of P. aeruginosa. CONCLUSIONS: Our study provides clear evidence that linear LEAP2 exhibits better antibacterial activity than oxidised LEAP2, thereby confirming, for the first time, this phenomenon in fish.


Assuntos
Sequência de Aminoácidos , Animais , Relação Estrutura-Atividade , Doenças dos Peixes/microbiologia , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/genética , Proteínas de Peixes/genética , Proteínas de Peixes/química , Dissulfetos/química , Filogenia , Aeromonas hydrophila/efeitos dos fármacos , Sequência de Bases
4.
J Environ Manage ; 362: 121320, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38843750

RESUMO

The efficient removal of volatile sulfur compounds (VSCs), such as dimethyl sulfide (DMS), dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS), is crucial due to their foul odor and corrosive potential in sewer systems. Biofilters (BFs) offer promise for VSCs removal, but face challenges related to pH control and changing conditions at full scale. Two BFs, operated under acidophilic conditions for 78 days, were evaluated for their performance at varying inlet concentrations and empty bed residence times (EBRTs). BF1, incorporating 4-6 mm marble limestone for pH control, outperformed BF2, which used NaHCO3 in the nutrient solution. BF1 displayed better resilience, maintained a stable pH of 4.6 ± 0.6, and achieved higher maximum elimination capacities (ECmax, 41 mg DMS m-3 h-1 (RE 38.3%), 146 mg DMDS m-3 h-1 (RE 83.1%), 47 mg DMTS m-3 h-1 (RE 93.1%)) at an EBRT of 56 s compared to BF2 (9 mg DMS m-3 h-1 (RE 7.1%), 9 mg DMDS m-3 h-1 (RE 4.8%) and 11 mg DMTS m-3 h-1 (RE 26.6%)). BF2 exhibited pH stratification and decreased performance after feeding interruptions. The biodegradability of VSCs followed the order DMTS > DMDS > DMS, and several microorganisms were identified contributing to VSCs degradation in BF1, including Bacillus (14%), Mycobacterium (11%), Acidiphilium (7%), and Acidobacterium (3%).


Assuntos
Dissulfetos , Filtração , Sulfetos , Sulfetos/química , Concentração de Íons de Hidrogênio
5.
Pediatr Surg Int ; 40(1): 152, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847871

RESUMO

The aim of this study was to analyze the role of thiol/disulfide homeostasis (TDH) parameters as an indicator of oxidative stress in acute appendicitis (AA). PubMed, EMBASE, Web of Science, and Scopus databases were systematically searched. Studies reporting on TDH in AA (both complicated and uncomplicated cases) were included. The comparator group were healthy controls. The TDH domain was compared between the groups using anti-oxidant parameters, namely native thiol and total thiol levels, and native thiol/total thiol ratio; and oxidant parameters, namely disulfide level, disulfide/native thiol ratio, and disulfide/total thiol ratio. The statistical analysis was performed using a random-effects model. The methodological quality of the studies was assessed utilizing the Newcastle-Ottawa scale. Eleven studies with a total of 926 subjects, comprising 457 patients with uncomplicated appendicitis, 147 with complicated appendicitis, and 322 healthy controls were included. Our study demonstrated significantly increased oxidative stress in AA as compared to healthy controls in all TDH parameters and significantly lower total thiol levels in complicated AA as compared to uncomplicated AA. Due to a poor methodological quality in five out of eleven studies, future prospective studies with adequate power are essential to validate these observations and refine the diagnostic approaches to AA.


Assuntos
Apendicite , Biomarcadores , Dissulfetos , Homeostase , Estresse Oxidativo , Compostos de Sulfidrila , Apendicite/sangue , Apendicite/diagnóstico , Humanos , Compostos de Sulfidrila/sangue , Homeostase/fisiologia , Dissulfetos/sangue , Biomarcadores/sangue , Estresse Oxidativo/fisiologia , Doença Aguda
6.
Immunopharmacol Immunotoxicol ; 46(3): 408-416, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38816179

RESUMO

BACKGROUND: Myelodysplastic syndrome (MDS) is a prevalent hematological neoplastic disorder in clinics and its immunopathogenesis has garnered growing interest. Oral and intravenous arsenic agents have long been used to treat hematological malignancies. The main component of oral arsenic is realgar (arsenic disulfide), while arsenic trioxide is the main component of intravenous arsenic. METHODS: This study aimed to assess the effects of ATO and Realgar on the enhancement of peripheral blood, drug safety, and T cell immune status in the NUP98-HOXD13 (NHD13) mice model of MDS, specifically in the peripheral blood, spleen, and liver. RESULTS: The study findings indicate that realgar and arsenic trioxide (ATO) can improve peripheral hemogram in mice, whereas realgar promotes higher peripheral blood cell production than ATO. Furthermore, the clinical administration method and dose did not cause significant toxicity or side effects and thus can be considered safe. Coexistence and interconversion of hyperimmune function and immunosuppression in mice were also observed in this study. In addition, there were interactions between immune cells in the peripheral blood, spleen, and liver to regulate the immune balance of the body and activate immunity via T-cell activation. CONCLUSION: In summary, oral and intravenous arsenic agents are beneficial in improving peripheral hemogram and immunity in mice.


Assuntos
Trióxido de Arsênio , Arsenicais , Modelos Animais de Doenças , Síndromes Mielodisplásicas , Animais , Trióxido de Arsênio/administração & dosagem , Trióxido de Arsênio/farmacologia , Arsenicais/farmacologia , Arsenicais/administração & dosagem , Camundongos , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/imunologia , Sulfetos/farmacologia , Sulfetos/administração & dosagem , Dissulfetos/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Baço/efeitos dos fármacos , Baço/imunologia
7.
Bioresour Technol ; 401: 130761, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692370

RESUMO

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.


Assuntos
Biomassa , Cromo , Dissulfetos , Molibdênio , Águas Residuárias , Purificação da Água , Molibdênio/química , Dissulfetos/química , Adsorção , Águas Residuárias/química , Purificação da Água/métodos , Cromo/química , Galvanoplastia , Poluentes Químicos da Água , Soluções
8.
Rev Assoc Med Bras (1992) ; 70(4): e20231120, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716937

RESUMO

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.


Assuntos
Doença Celíaca , Dieta Livre de Glúten , Dissulfetos , Estresse Oxidativo , Cooperação do Paciente , Compostos de Sulfidrila , Humanos , Doença Celíaca/dietoterapia , Doença Celíaca/sangue , Estresse Oxidativo/fisiologia , Feminino , Masculino , Dissulfetos/sangue , Estudos Prospectivos , Compostos de Sulfidrila/sangue , Adulto , Indução de Remissão , Adulto Jovem , Adolescente , Pessoa de Meia-Idade , Imunoglobulina A/sangue , Transglutaminases/sangue
9.
Biomed Mater ; 19(4)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38772383

RESUMO

The traditional chemotherapeutic agents' disadvantages such as high toxicity, untargeting and poor water solubility lead to disappointing chemotherapy effects, which restricts its clinical application. In this work, novel size-appropriate and glutathione (GSH)-responsive nano-hydrogels were successfully prepared via the active ester method between chitosan (containing -NH2) and cross-linker (containing NHS). Especially, the cross-linker was elaborately designed to possess a disulfide linkage (SS) as well as two terminal NHS groups, namely NHS-SS-NHS. These functionalities endowed chitosan-based cross-linked scaffolds with capabilities for drug loading and delivery, as well as a GSH-responsive mechanism for drug release. The prepared nano-hydrogels demonstrated excellent performance applicable morphology, excellent drug loading efficiency (∼22.5%), suitable size (∼100 nm) and long-term stability. The prepared nano-hydrogels released over 80% doxorubicin (DOX) after incubation in 10 mM GSH while a minimal DOX release less than 25% was tested in normal physiological buffer (pH = 7.4). The unloaded nano-hydrogels did not show any apparent cytotoxicity to A 549 cells. In contrast, DOX-loaded nano-hydrogels exhibited marked anti-tumor activity against A 549 cells, especially in high GSH environment. Finally, through fluorescent imaging and flow cytometry analysis, fluorescein isothiocyanate-labeled nano-hydrogels show obvious specific binding to the GSH high-expressing A549 cells and nonspecific binding to the GSH low-expressing A549 cells. Therefore, with this cross-linking approach, our present finding suggests that cross-linked chitosan nano-hydrogel drug carrier improves the anti-tumor effect of the A 549 cells and may serve as a potential injectable delivery carrier.


Assuntos
Antineoplásicos , Quitosana , Reagentes de Ligações Cruzadas , Doxorrubicina , Glutationa , Hidrogéis , Quitosana/química , Humanos , Doxorrubicina/farmacologia , Doxorrubicina/química , Glutationa/química , Glutationa/metabolismo , Hidrogéis/química , Reagentes de Ligações Cruzadas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Linhagem Celular Tumoral , Células A549 , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Dissulfetos/química , Preparações de Ação Retardada/química
10.
Nat Commun ; 15(1): 3827, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714735

RESUMO

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.


Assuntos
Domínio Catalítico , Proteases 3C de Coronavírus , Cisteína , Dissulfetos , Oxirredução , SARS-CoV-2 , Dissulfetos/química , Dissulfetos/metabolismo , SARS-CoV-2/metabolismo , SARS-CoV-2/química , Proteases 3C de Coronavírus/metabolismo , Proteases 3C de Coronavírus/química , Cisteína/química , Cisteína/metabolismo , Cristalografia por Raios X , Humanos , Modelos Moleculares , Multimerização Proteica , COVID-19/virologia
11.
J Proteomics ; 301: 105194, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38723850

RESUMO

This study explores the disulfide bridges present in the human milk proteome by a novel approach permitting both positional identification and relative quantification of the disulfide bridges. Human milk from six donors was subjected to trypsin digestion without reduction. The digested human milk proteins were analyzed by nanoLC-timsTOF Pro combined with data analysis using xiSEARCH. A total of 85 unique disulfide bridges were identified in 25 different human milk proteins. The total relative abundance of disulfide bridge-containing peptides constituted approximately 5% of the total amount of tryptic-peptides. Seven inter-molecular disulfide bridges were identified between either α-lactalbumin and lactotransferrin (5) or αS1-casein and κ-casein (2). All cysteines involved in the observed disulfide bridges of α-lactalbumin and lactotransferrin were mapped onto protein models using AlphaFold2 Multimer to estimate the length of the observed disulfide bridges. The lengths of the disulfide bridges of lactotransferrin indicate a potential for multi- or poly-merization of lactotransferrin. The high number of intramolecular lactotransferrin disulfide bridges identified, suggests that these are more heterogeneous than previously presumed. SIGNIFICANCE: Disulfide-bridges in the human milk proteome are an often overseen post-transaltional modification. Thus, mapping the disulfide-bridges, their positions and relative abundance, are valuable new knowledge needed for an improved understanding of human milk protein behaviour. Although glycosylation and phosphorylation have been described, even less information is available on the disulfide bridges and the disulfide-bridge derived protein complexes. This is important for future work in precision fermentation for recombinant production of human milk proteins, as this will highlight which disulfide-bridges are naturally occouring in human milk proteins. Further, this knowledge would be of value for the infant formula industry as it provides more information on how to humanize bovine-milk based infant formula. The novel method developed here can be broadly applied in other biological systems as the disulfid-brigdes are important for the structure and functionality of proteins.


Assuntos
Dissulfetos , Leite Humano , Proteoma , Proteômica , Humanos , Leite Humano/química , Dissulfetos/química , Dissulfetos/análise , Proteômica/métodos , Proteoma/análise , Lactoferrina/análise , Lactoferrina/química , Proteínas do Leite/análise , Proteínas do Leite/química , Lactalbumina/química , Lactalbumina/análise , Feminino
12.
Anal Chem ; 96(21): 8243-8248, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38733603

RESUMO

Native mass spectrometry (MS) continues to enjoy growing popularity as a means of providing a wealth of information on noncovalent biopolymer assemblies ranging from composition and binding stoichiometry to characterization of the topology of these assemblies. The latter frequently relies on supplementing MS measurements with limited fragmentation of the noncovalent complexes in the gas phase to identify the pairs of neighboring subunits. While this approach has met with much success in the past two decades, its implementation remains difficult (and the success record relatively modest) within one class of noncovalent assemblies: protein complexes in which at least one binding partner has multiple subunits cross-linked by disulfide bonds. We approach this problem by inducing chemical reduction of disulfide bonds under nondenaturing conditions in solution followed by native MS analysis with online buffer exchange to remove unconsumed reagents that are incompatible with the electrospray ionization process. While this approach works well with systems comprised of thiol-linked subunits that remain stable upon reduction of the disulfide bridges (such as immunoglobulins), chemical reduction frequently gives rise to species that are unstable (prone to aggregation). This problem is circumvented by taking advantage of the recently introduced cross-path reactive chromatography platform (XPRC), which allows the disulfide reduction to be carried out in-line, thereby minimizing the loss of metastable protein subunits and their noncovalent complexes with the binding partners prior to MS analysis. The feasibility of this approach is demonstrated using hemoglobin complexes with haptoglobin 1-1, a glycoprotein consisting of four polypeptide chains cross-linked by disulfide bonds.


Assuntos
Dissulfetos , Oxirredução , Dissulfetos/química , Espectrometria de Massas , Subunidades Proteicas/química , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo
13.
Langmuir ; 40(21): 11098-11105, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38739904

RESUMO

Disulfide bonding has attracted intense interest in the tumor intracellular microenvironment-activated drug delivery systems (DDSs) in the last decades. Although various molecular structures of redox-responsive disulfide-containing DDSs have been developed, no investigation was reported on the effect of aggregation structures. Here, the effect of aggregation structures on pH/GSH dual-triggered drug release was investigated with the simplest pH/GSH dual-triggered doxorubicin-based drug self-delivery system (DSDS), the disulfide/α-amide-bridged doxorubicin dimeric prodrug (DDOX), as a model. By fast precipitation or slow self-assembly, DDOX nanoparticles were obtained. With similar diameters, they exhibited different pH/GSH dual-triggered drug releases, demonstrating the effect of aggregation structures. The π-π stacking in different degrees was revealed by the UV-vis, fluorescence, and BET analysis of the DDOX nanoparticles. The effect of the π-π stacking between the dimeric prodrug and its activated products on drug release was also explored with the molecular simulation approach. The finding opens new ideas in the design of high-performance DDSs for future precise tumor treatment.


Assuntos
Dissulfetos , Doxorrubicina , Liberação Controlada de Fármacos , Glutationa , Pró-Fármacos , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Concentração de Íons de Hidrogênio , Dissulfetos/química , Glutationa/química , Amidas/química , Nanopartículas/química , Dimerização , Portadores de Fármacos/química
14.
J Mater Chem B ; 12(21): 5024-5038, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38712810

RESUMO

Composite materials can take advantages of the functional benefits of multiple pure nanomaterials to a greater degree than single nanomaterials alone. The UCNPs-MoS2 composite is a nano-application platform that combines upconversion luminescence and photothermal properties. Upconversion nanoparticles (UCNPs) are inorganic nanomaterials with long-wavelength excitation and short-wavelength tunable emission capabilities, and are able to effectively convert near-infrared (NIR) light into visible light for increased photostability. However, UCNPs have a low capacity for absorbing visible light, whereas MoS2 shows better absorption in the ultraviolet and visible regions. By integrating the benefits of UCNPs and MoS2, UCNPs-MoS2 nanocomposites can convert NIR light with a higher depth of detection into visible light for application with MoS2 through fluorescence resonance energy transfer (FRET), which compensates for the issues of MoS2's low tissue penetration light-absorbing wavelengths and expands its potential biological applications. Therefore, starting from the construction of UCNPs-MoS2 nanoplatforms, herein, we review the research progress in biological applications, including biosensing, phototherapy, bioimaging, and targeted drug delivery. Additionally, the current challenges and future development trends of UCNPs-MoS2 nanocomposites for biological applications are also discussed.


Assuntos
Dissulfetos , Molibdênio , Nanocompostos , Molibdênio/química , Dissulfetos/química , Nanocompostos/química , Humanos , Técnicas Biossensoriais , Animais , Fototerapia/métodos , Sistemas de Liberação de Medicamentos
15.
J Phys Chem B ; 128(19): 4590-4601, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38701111

RESUMO

Cofilin, a key actin-binding protein, orchestrates the dynamics of the actomyosin network through its actin-severing activity and by promoting the recycling of actin monomers. Recent experiments suggest that cofilin forms functionally distinct oligomers via thiol post-translational modifications (PTMs) that promote actin nucleation and assembly. Despite these advances, the structural conformations of cofilin oligomers that modulate actin activity remain elusive because there are combinatorial ways to oxidize thiols in cysteines to form disulfide bonds rapidly. This study employs molecular dynamics simulations to investigate human cofilin 1 as a case study for exploring cofilin dimers via disulfide bond formation. Utilizing a biasing scheme in simulations, we focus on analyzing dimer conformations conducive to disulfide bond formation. Additionally, we explore potential PTMs arising from the examined conformational ensemble. Using the free energy profiling, our simulations unveil a range of probable cofilin dimer structures not represented in current Protein Data Bank entries. These candidate dimers are characterized by their distinct population distributions and relative free energies. Of particular note is a dimer featuring an interface between cysteines 139 and 147 residues, which demonstrates stable free energy characteristics and intriguingly symmetrical geometry. In contrast, the experimentally proposed dimer structure exhibits a less stable free energy profile. We also evaluate frustration quantification based on the energy landscape theory in the protein-protein interactions at the dimer interfaces. Notably, the 39-39 dimer configuration emerges as a promising candidate for forming cofilin tetramers, as substantiated by frustration analysis. Additionally, docking simulations with actin filaments further evaluate the stability of these cofilin dimer-actin complexes. Our findings thus offer a computational framework for understanding the role of thiol PTM of cofilin proteins in regulating oligomerization, and the subsequent cofilin-mediated actin dynamics in the actomyosin network.


Assuntos
Citoesqueleto de Actina , Dissulfetos , Simulação de Dinâmica Molecular , Dissulfetos/química , Humanos , Citoesqueleto de Actina/química , Citoesqueleto de Actina/metabolismo , Cofilina 1/química , Cofilina 1/metabolismo , Multimerização Proteica , Actinas/química , Actinas/metabolismo , Fatores de Despolimerização de Actina/química , Fatores de Despolimerização de Actina/metabolismo , Termodinâmica
16.
J Agric Food Chem ; 72(23): 13228-13239, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38810088

RESUMO

Limited alliinase resources cause difficulties in the biosynthesis of thiosulfinates (e.g., allicin), restricting their applications in the agricultural and food industries. To effectively biosynthesize thiosulfinates, this study aimed to excavate bacterial alliinase resources and elucidate their catalytic properties. Two bacterial cystathionine ß-lyases (MetCs) possessing high alliinase activity (>60 U mg -1) toward L-(-)-alliin were identified from Allium sativum rhizosphere isolates. Metagenomic exploration revealed that cystathionine ß-lyase from Bacillus cereus (BcPatB) possessed high activity toward both L-(±)-alliin and L-(+)-alliin (208.6 and 225.1 U mg -1), respectively. Although these enzymes all preferred l-cysteine S-conjugate sulfoxides as substrates, BcPatB had a closer phylogenetic relationship with Allium alliinases and shared several similar features with A. sativum alliinase. Interestingly, the Trp30Ile31Ala32Asp33 Met34 motif in a cuspate loop of BcPatB, especially sites 31 and 32 at the top of the motif, was modeled to locate near the sulfoxide of L-(+)-alliin and is important for substrate stereospecificity. Moreover, the stereoselectivity and activity of mutants I31V and A32G were higher toward L-(+)-alliin than those of mutant I31L/D33E toward L-(-)-alliin. Using bacterial alliinases and chemically synthesized substrates, we obtained thiosulfinates with high antimicrobial and antinematode activities that could provide insights into the protection of crops and food.


Assuntos
Proteínas de Bactérias , Alho , Especificidade por Substrato , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Alho/química , Alho/enzimologia , Alho/genética , Ácidos Sulfínicos/química , Ácidos Sulfínicos/metabolismo , Bacillus cereus/enzimologia , Bacillus cereus/genética , Bacillus cereus/metabolismo , Dissulfetos/química , Dissulfetos/metabolismo , Filogenia , Estereoisomerismo , Sequência de Aminoácidos , Bactérias/enzimologia , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Cinética , Liases de Carbono-Enxofre/metabolismo , Liases de Carbono-Enxofre/genética , Liases de Carbono-Enxofre/química , Cisteína/análogos & derivados
17.
Nano Lett ; 24(23): 6948-6956, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38810209

RESUMO

The concept of cross-sensor modulation, wherein one sensor modality can influence another's response, is often overlooked in traditional sensor fusion architectures, leading to missed opportunities for enhancing data accuracy and robustness. In contrast, biological systems, such as aquatic animals like crayfish, demonstrate superior sensor fusion through multisensory integration. These organisms adeptly integrate visual, tactile, and chemical cues to perform tasks such as evading predators and locating prey. Drawing inspiration from this, we propose a neuromorphic platform that integrates graphene-based chemitransistors, monolayer molybdenum disulfide (MoS2) based photosensitive memtransistors, and triboelectric tactile sensors to achieve "Super-Additive" responses to weak chemical, visual, and tactile cues and demonstrate contextual response modulation, also referred to as the "Inverse Effectiveness Effect." We hold the view that integrating bio-inspired sensor fusion principles across various modalities holds promise for a wide range of applications.


Assuntos
Astacoidea , Grafite , Molibdênio , Tato , Animais , Molibdênio/química , Grafite/química , Dissulfetos/química
18.
ACS Appl Bio Mater ; 7(5): 3337-3345, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38700956

RESUMO

A stimuli-responsive drug delivery nanocarrier with a core-shell structure combining photothermal therapy and chemotherapy for killing cancer cells was constructed in this study. The multifunctional nanocarrier ReS2@mSiO2-RhB entails an ReS2 hierarchical nanosphere coated with a fluorescent mesoporous silica shell. The three-dimensional hierarchical ReS2 nanostructure is capable of effectively absorbing near-infrared (NIR) light and converting it into heat. These ReS2 nanospheres were generated by a hydrothermal synthesis process leading to the self-assembly of few-layered ReS2 nanosheets. The mesoporous silica shell was further coated on the surface of the ReS2 nanospheres through a surfactant-templating sol-gel approach to provide accessible mesopores for drug uploading. A fluorescent dye (Rhodamine B) was covalently attached to silica precursors and incorporated during synthesis in the mesoporous silica walls toward conferring imaging capability to the nanocarrier. Doxorubicin (DOX), a known cancer drug, was used in a proof-of-concept study to assess the material's ability to function as a drug delivery carrier. While the silica pores are not capped, the drug molecule loading and release take advantage of the pH-governed electrostatic interactions between the drug and silica wall. The ReS2@mSiO2-RhB enabled a drug loading content as high as 19.83 mg/g doxorubicin. The ReS2@mSiO2-RhB-DOX nanocarrier's cumulative drug release rate at pH values that simulate physiological conditions showed significant pH responsiveness, reaching 59.8% at pH 6.8 and 98.5% and pH 5.5. The in vitro testing using HeLa cervical cancer cells proved that ReS2@mSiO2-RhB-DOX has a strong cancer eradication ability upon irradiation with an NIR laser owing to the combined drug delivery and photothermal effect. The results highlight the potential of ReS2@mSiO2-RhB nanoparticles for combined cancer therapy in the future.


Assuntos
Doxorrubicina , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Teste de Materiais , Nanopartículas , Tamanho da Partícula , Terapia Fototérmica , Rênio , Dióxido de Silício , Dióxido de Silício/química , Humanos , Doxorrubicina/farmacologia , Doxorrubicina/química , Concentração de Íons de Hidrogênio , Nanopartículas/química , Rênio/química , Rênio/farmacologia , Dissulfetos/química , Porosidade , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/síntese química , Sobrevivência Celular/efeitos dos fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Portadores de Fármacos/química , Células HeLa
19.
Talanta ; 276: 126256, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38762977

RESUMO

Endotoxins, also known as lipopolysaccharides (LPS), are present within the cell walls of Gram-negative bacteria and are released upon cellular death, which can pose a significant risk to human and animal health. Due to the minimal amount of endotoxin required to trigger an inflammatory response in human body, the demand for sensitive methods with low endotoxin detection limits is essential necessary. This paper presents a straightforward aptamer sensor which can enhance the conductivity and specific surface area of molybdenum disulfide (MoS2) by incorporating carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) and polyaniline (PANI). Doping with gold nanoparticles (AuNPs) improves biocompatibility and sensitivity while providing binding sites for thiolated endotoxin-binding aptamers (LBA). This biosensor achieved a remarkable detection limit as low as 0.5 fg mL-1, enabling trace-level identification of LPS. It also exhibits excellent repeatability, selectivity, and stability, facilitating rapid and accurate LPS detection. Moreover, this method demonstrates high recovery rates and specificity for LPS analysis in food samples, showcasing its promising application prospects in trace-level LPS detection within the food industry.


Assuntos
Compostos de Anilina , Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Dissulfetos , Ouro , Lipopolissacarídeos , Molibdênio , Nanotubos de Carbono , Nanotubos de Carbono/química , Compostos de Anilina/química , Dissulfetos/química , Molibdênio/química , Técnicas Biossensoriais/métodos , Aptâmeros de Nucleotídeos/química , Lipopolissacarídeos/análise , Ouro/química , Nanopartículas Metálicas/química , Limite de Detecção , Endotoxinas/análise
20.
Talanta ; 276: 126281, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38788386

RESUMO

In the medical field, changes in interleukin-6 (IL-6) concentration serve as essential biomarkers for monitoring and diagnosing various conditions, including acute inflammatory responses such as those seen in trauma and burns, and chronic illnesses like cancer. This paper detailed a label-free electrochemical aptamer sensor designed for IL-6 quantification. A composite material consisting of Ti3C2Tx and MoS2 was successfully synthesized to fabricate this sensor. The synergistic effect of MoS2's catalytic action on hydrogen peroxide (H2O2), used as a signalling marker, when combined with the exceptional conductivity and large specific surface area of Ti3C2Tx, not only enables an increased loading of MoS2 but also significantly boosts the electrochemical response. The in situ-reduced Au NPs provided stable immobilization sites for DNA aptamers (DNAapt) and facilitated electron transfer, ensuring accurate IL-6 recognition. Under optimal conditions, the aptamer sensor exhibited a wide linear range (5 pg/mL to 100 ng/mL) and a low limit of detection (LOD) of 2.9 pg/mL. Its sensing performance in human serum samples highlights its potential as a promising clinical analysis tool.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Dissulfetos , Técnicas Eletroquímicas , Ouro , Interleucina-6 , Nanopartículas Metálicas , Molibdênio , Titânio , Interleucina-6/sangue , Interleucina-6/análise , Aptâmeros de Nucleotídeos/química , Molibdênio/química , Humanos , Ouro/química , Técnicas Eletroquímicas/métodos , Titânio/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Dissulfetos/química , Limite de Detecção , Peróxido de Hidrogênio/química
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