Transforming growth factor beta 3 (TGF-β3) is a homodimeric cytokine with potential therapeutic applications in wound healing, tissue engineering and regenerative medicine. Production of recombinant TGF-β3 in Escherichia coli faces significant challenges due to TGF-β3’s propensity for misfolding and aggregation, driven by a high disulfide bond content and low aqueous solubility. To address these limitations, the impacts of substituting non-conserved cysteine residues C7, C16 and C77 with serine on TGF-β3 folding, dimerization and activity were investigated. Whilst C7 and C16 form an intra-chain disulfide bond, C77 forms an inter-chain disulfide bond stabilizing dimer formation. Our results showed that the C7S, C16S double cysteine mutant protein exhibited reduced aggregation, increased dimer formation, and maintained wild-type biological activity in nano-luciferase reporter gene assay. In contrast, both C77S single and C7S, C16S, C77S triple mutants were purified predominantly in monomeric forms and displayed about 2.5-fold reduced activities. Our findings highlight the roles of the non-conserved C7, C16 and C77 cysteine residues in TGF-β3 folding and aggregation. The identification of the C7S, C16S mutant as a more soluble protein with wild-type TGF-β3 activity offers a promising strategy for improving recombinant TGF-β3 production to facilitate therapeutic applications. This study underscores the importance of targeted cysteine engineering to overcome the inherent challenges associated with the production of TGF-β3 and related complex disulfide-rich proteins.

Manganese -based oxides are deemed to be prospective cathode materials for aqueous zinc -ion batteries (ZIBs). Nevertheless, their practical application was hampered by the slow zinc -ion diffusion dynamics and the instability of MnO2 structure. The 8-MnO2/MXene cathodes have been investigated to overcome the inherent defects of 8-MnO2 and significantly improve the performance of ZIBs. However, these 8-MnO2/MXene cathodes suffer from high -temperature, high-pressure, time-consuming or complicated production processes. To address these issues, 8-MnO2/Ti3C2Tx cathode was synthesized by a one-step in -situ growth strategy under mild conditions. The 8-MnO2/Ti3C2Tx cathode can take advantages of the large specific capacity of 8-MnO2 and the high conductivity of Ti3C2Tx nanosheets. Besides, the highly conductive Ti3C2Tx scaffolds efficaciously suppress the irreversible structural damage of 8-MnO2. Therefore, the ZIB assembled with the 8-MnO2/Ti3C2Tx cathode demonstrates significantly improved electrochemical behavior with a large specific capacity of 320.6 mAh g-1 at 0.1 A g-1, excellent rate capability of 153.0 mAh g-1 at 3.0 A g-1, high energy density of 440.0 Wh kg- 1 at 136.6 W kg - 1, and good cyclability with a capacity retention of 70.2 % after 1500 cycles, significantly outperforming the 8-MnO2 cathode. The findings of this study suggest that the 8-MnO2/Ti3C2Tx composite holds promise as a potential cathode for high-performance aqueous ZIBs.

Mitochondria are essential organelles of eukaryotic cells and thus mitochondrial proteome is under constant quality control and remodelling. Yme1 is a multi-functional protein and subunit of the homo-hexametric complex i-AAA proteinase. Yme1 plays vital roles in the regulation of mitochondrial protein homeostasis and mitochondrial plasticity, ranging from substrate degradation to the regulation of protein functions involved in mitochondrial protein biosynthesis, energy production, mitochondrial dynamics, and lipid biosynthesis and signalling. In this mini review, we focus on discussing the current understanding of the roles of Yme1 in mitochondrial protein import via TIM22 and TIM23 pathways, oxidative phosphorylation complex function, as well as mitochondrial lipid biosynthesis and signalling, as well as a brief discussion of the role of Yme1 in modulating mitochondrial dynamics.

In this study, SiO@graphite@C@Al2O3 (SiO@G@C@A) composites are synthesized by varying the content of Al2O3, and their morphology and structure and their electrochemical performance are investigated in detail. The results indicate that the SiO/G@C@A-2 composite exhibits a specific capacity of 977.1 mA h g(-1) at a current density of 0.1 A g(-1) with a coulombic efficiency of 71.15%. Even after 100 cycles at a current density of 0.5 A g(-1), it retains a delithiated specific capacity of 640.7 mA h g(-1) and a capacity retention rate of 73.56%. Moreover, when the current density is raised to 2 A g(-1), it maintains a delithiated capacity of 568.4 mA h g(-1) and a capacity retention rate of 58.51%. The excellent electrochemical performance is ascribed to the synergistic effect of different components. The inclusion of graphite enhances overall conductivity while mitigating the volume expansion of the SiO. The application of asphalt pyrolytic carbon as a coating effectively isolates the SiO from the electrolyte, further reducing volume expansion and enhancing conductivity. The introduction of Al2O3 can absorb trace amounts of hydrogen fluoride (HF) generated during charge and discharge processes. Additionally, it facilitates the formation of an AlF3 film on the particle surfaces, which hinders and decelerates electrolyte dissolution into the electrode. The prepared composites exhibit promising prospects as lithium-ion battery anode materials. [GRAPHICS] .

Graphene oxide (GO) has attracted huge attention in biomedical sciences due to its outstanding properties and potential applications. In this study, we synthesized GO using our recently developed 1-pyrenebutyric acid-assisted method and assessed how the GO as a filler influences the mechanical properties of GO–gelatine nanocomposite dry films as well as the cytotoxicity of HEK-293 cells grown on the GO–gelatine substrates. We show that the addition of GO (0–2%) improves the mechanical properties of gelatine in a concentration-dependent manner. The presence of 2 wt% GO increased the tensile strength, elasticity, ductility, and toughness of the gelatine films by about 3.1-, 2.5-, 2-, and 8-fold, respectively. Cell viability, apoptosis, and necrosis analyses showed no cytotoxicity from GO. Furthermore, we performed circular dichroism, X-ray diffraction, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy analyses to decipher the interactions between GO and gelatine. The results show, for the first time, that GO enhances the mechanical properties of gelatine by forming non-covalent intermolecular interactions with gelatine at its amorphous or disordered regions. We believe that our findings will provide new insight and help pave the way for potential and wide applications of GO in tissue engineering and regenerative biomedicine.

To achieve oil/water separation using both absorption and filtration regardless of the oil/water density relationship, the super-hydrophilic/underwater super-oleophobic graphene oxide coated melamine sponge (GO@MS ) and super-hydrophobic/super-oleophilic reduced graphene oxide coated melamine sponge (rGO@MS) were prepared via dip-coating of graphene oxide (GO) sheets onto melamine sponge (MS) and subsequent chemical reduction, respectively. The structures of the GO@MS and rGO@MS were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Raman spectra, and X-ray diffraction (XRD). Both GO@MS and rGO@MS can preserve their original wettability in harsh environments containing acidic, alkaline, saline, and hot waters. The GO@MS and rGO@MS show excellent capability for selective absorption of water and oil respectively, with high capacities of 72.3-136.5 g g(-1) and excellent recyclability. The compressed GO@MS and rGO@MS also exhibit high separation efficiency of about 99% and ultra-high permeation flux above 1.62 x 10(5) L m(-2) h(-)(1) for separating different oil/water mixtures containing light and heavy oils through filtration driven by gravity, respectively. Furthermore, a bidirectional separation setup assembled with the compressed GO@MS and rGO@MS was constructed, which demonstrates high efficiency for continuously separating different oil/water mixtures of any oil density.

Zinc oxide is a popular semiconductor used in catalysts due to its wide bandgap and high exciton binding energy. However, the photocatalytic performance of ZnO was compromised by its insufficient electron-hole separation efficiency and electron transfer rate. Herein, ZnO-reduced graphene oxide (rGO) composite solid catalyst was synthesized by one-step electrodeposition method on FTO substrate using lithium perchlorate (LiClO4) as the supporting electrolyte. Scanning electron microscopy, Raman, Fourier Transform Infrared, and XRD characterizations confirmed the deposition of ZnO and the reduction of graphene oxide Owing to the cooperative effect between rGO and ZnO, the as-prepared ZnO-rGO composites show much enhanced photocatalytic degradation ability compared with pure ZnO nanorods. By optimizing the conditions of electrodeposition of ZnO-rGO composites, the degradation rate of methylene blue can reach 99.1% within 120 min. Thus, the simple preparation and the excellent performance could endow the ZnO-rGO composites with promising application in practical dye-polluted water treatment.

We fabricated reduced graphene oxide (rGO)-reinforced Al2O3 composites by spark plasma sintering and studied the effect of graphene oxide (GO) dimensions on the microstructure and mechanical properties of composites. The thin GO led to both grain size refinement and grain boundary pinning effects. The Al2O3 composite reinforced by thin and large GO had higher hardness than that reinforced by thick and small GO. The addition of thick GO leads to a reduction of hardness and generation of lateral cracks at the Al2O3 grain boundaries under indentation due to low rGO interlayer strength. The rGO distribution in the Al2O3 matrix was studied. A model calculation showed that the spacing between two parallel rGO platelets was one Al2O3 grain at rGO addition of 0.77 wt%. We concluded that the increased hardness of rGO/Al2O3 composites is due to the fine grain size and thin rGO at Al2O3 grain boundaries.

The chemical reduction efficiencies of graphene oxide (GO) are critically important in achieving graphene-like properties in reduced graphene oxide (rGO). In this study, we assessed GO lateral size and its degree of oxidation effect on its chemical reduction efficiency in both suspension and film and the electrical conductivity of the corresponding rGO films. We show that while GO-reduction efficiency increases with the GO size of lower oxidation in suspension, the trend is opposite for film. FESEM, XRD, and Raman analyses reveal that the GO reduction efficiency in film is affected not only by GO size and degree of oxidation but also by its interlayer spacing (restacking) and the efficiency is tunable based on the use of mixed GO. Moreover, we show that the electrical conductivity of rGO films depends linearly on the C/O and Raman I-D/I-G ratio of rGO and not the lateral size of GO. In this study, an optimal chemical reduction was achieved using premixed large and small GO (L/SGO) at a ratio of 3:1 (w/w). Consequently, the highest electrical conductivity of 85,283 S/m was achieved out of all rGO films reported so far. We hope that our findings may help to pave the way for a simple and scalable method to fabricate tunable, electrically conductive rGO films for electronic applications.

Mitochondrial i-AAA proteinase Yme1 is a multifunctional protein that plays important roles in maintaining mitochondrial protein homeostasis and regulating biogenesis and function of mitochondrial proteins. However, due to the complex interplay of mitochondria and the multifunctional nature of Yme1, how Yme1 affects mitochondrial function and protein homeostasis is still poorly understood. In this study, we investigated how YME1 deletion affects yeast Saccharomyces cerevisiae growth, chronological life span, mitochondrial protein homeostasis and function, with a focus on the mitochondrial oxidative phosphorylation (OXPHOS) complexes. Our results show that whilst the YME1 deleted cells grow poorly under respiratory conditions, they grow similar to wild-type yeast under fermentative conditions. However, the chronological life span is impaired, indicating that Yme1 plays a key role in longevity. Using highly enriched mitochondrial extract and proteomic analysis, we show that the abundances of many mitochondrial proteins are altered by YME1 deletion. Several components of the respiratory chain complexes II, III, IV and V were significantly decreased, suggesting that Yme1 plays an important role in maintaining the level and function of complexes II-V. This result was confirmed using blue native-PAGE and in-solution-based enzyme activity assays. Taken together, this study shows that Yme1 plays an important role in the chronological life span and mitochondrial protein homeostasis and has deciphered its function in maintaining the activity of mitochondrial OXPHOS complexes.

Zinc oxide (ZnO) nanostructures are commonly used as semiconductor films for the photoanodes of dyesensitized solar cells (DSSCs). However, the photoelectric conversion efficiency (PCE) of DSSCs with ZnO photoanode was compromised by the instability of the physical and chemical properties of ZnO. In this paper, ZnOreduced graphene oxide (rGO) composite photoanodes were obtained by a one-step electrodeposition method, and the photoelectric performance of the assembled DSSCs were measured. By comparing the PCE and other photoelectric parameters of the DSSCs constructed by the ZnO-rGO photoanodes deposited under different deposition potentials and times, the DSSCs achieved the best performance with the photoelectric conversion efficiency (PCE), open circuit voltage (Voc), short-circuit current density (Jsc), and fill factor (FF) of 1.07%, 386.15 mV, 4.65 mA cm-2, and 0.59, respectively.

Fabrication of filtration membranes with opposite wettability for the separation of immiscible oil/water mixture has aroused extensive attention owing to the avoidance of oil/water density relationship limitation. Herein, we demonstrate a low-cost, mild and environment-friendly method to prepare underwater superoleophobic graphene oxide (GO) coated fabric through dip-coating of GO nanosheets onto cotton fabric, and the superhydrophilic GO coated fabric can be converted to superhydrophobic reduced graphene oxide (rGO) coated fabric after chemical reduction of the coated GO. The GO and rGO coated fabrics show excellent efficiencies for unidirectional separation of various light oils and heavy oils from water, respectively. Both types of fabrics could maintain their original wettability in harsh environments, and demonstrate high efficiency and recyclability for the separation of oil/water mixtures containing hot water, acid and salt. Furthermore, a T-shaped bidirectional separation device was devised by integrating the two fabrics with opposite wettability, which can realize high-efficient continuous separation of various oil/water mixtures regardless of the oil density.

Graphene oxide (GO) has received great attention for its potential applications. The formation of large-size GO is favoured for its high mechanical properties and low structural defects. Improved Hummers' method is a commonly used method for GO synthesis. However, the production of large-size GO is often limited by the inevitable GO fragmentation caused by excessive oxidation and mechanical exfoliation. Here, we discovered that adding 1-pyrenebutyric acid (1-PBA) during the pre-treatment of graphite with sulfuric acid protects graphite from excessive oxidation and facilitates its self-exfoliation. Consequently, 99% monolayer GO with an average lateral size of 116 mu m was obtained without external forces. Furthermore, X-ray photoelectron spectroscopy and Raman analyses showed that the large-size GO synthesized in the presence of 1-PBA has a high C/O ratio of 3.62 and low Raman I-D/I-G ratio of 0.83, so it has low structural defects. A mechanism of 1-PBA during GO synthesis was proposed. Moreover, we investigated the mechanical property of GO synthesized with 1-PBA and how the lateral size of GO affects the mechanical properties of GO films. Our results showed that the LGO film displayed the highest tensile strength (127 MPa) due to a denser, more aligned and compact structure than other GO films. (C) 2021 Elsevier Ltd. All rights reserved.

Erv1 (EC number 1.8.3.2) is an essential mitochondrial enzyme catalyzing protein import and oxidative folding in the mitochondrial intermembrane space. Erv1 has both oxidase and cytochrome c reductase activities. While both Erv1 and cytochrome c were reported to be membrane associated in mitochondria, it is unknown how the mitochondrial membrane environment may affect the function of Erv1. Here, in this study, we used liposomes to mimic the mitochondrial membrane and investigated the effect of liposomes and cardiolipin on the folding and function of yeast Erv1. Enzyme kinetics of both the oxidase and cytochrome c reductase activity of Erv1 were studied using oxygen consumption analysis and spectroscopic methods. Our results showed that the presence of liposomes has mild impacts on Erv1 oxidase activity, but significantly inhibited the catalytic efficiency of Erv1 cytochrome c reductase activity in a cardiolipin-dependent manner. Taken together, the results of this study provide important insights into the function of Erv1 in the mitochondria, suggesting that molecular oxygen is a better substrate than cytochrome c for Erv1 in the yeast mitochondria.

Abstract Objectives It has been over 10 years since the first report of autoantibodies directed against phenylalanyl tRNA synthetase (anti-Zo) in a patient with features of the anti-synthetase syndrome. In that time no further cases have been published. Here we aim to characterize more fully the clinical phenotype of anti-Zo–associated myositis by describing the clinical features of nine patients. Methods Anti-Zo was identified by protein-immunoprecipitation in patients referred for extended spectrum myositis autoantibody testing at our laboratory. Results were confirmed by immunodepletion using a reference serum. Medical records were retrospectively reviewed to provide detailed information of the associated clinical phenotype for all identified patients. Where possible, HLA genotype was imputed using Illumina protocols. Results Nine patients with anti-Zo were identified. The median age at disease onset was 51 years, and six patients were female. Seven patients had evidence of inflammatory muscle disease, seven of interstitial lung disease and six of arthritis. The reported pattern of interstitial lung disease varied with usual interstitial pneumonia, non-specific interstitial pneumonia and organizing pneumonia all described. Other features of the anti-synthetase syndrome such as RP and mechanics hands were common. HLA data was available for three patients, all of whom had at least one copy of the HLA 8.1 ancestral haplotype. Conclusion Patients with anti-Zo presenting with features of the anti-synthetase syndrome and interstitial lung disease is a common finding. Like other myositis autoantibodies, there is likely to be a genetic association with the HLA 8.1 ancestral haplotype.

We report a mild, inexpensive, environment-friendly method to fabricate graphene oxide (GO) and reduced graphene oxide (RGO) coated meshes with superhydrophilicity/underwater superoleophobicity and superhydrophobicity/superoleophilicity through scrape coating of GO nanosheets onto stainless steel mesh and electrochemical reduction of the GO coated mesh, respectively. The GO coated meshes exhibit high efficiency for unidirectional separation of mixtures of water and various light oils, while the RGO coated meshes show excellent capability of separating various heavy oils from water. Both types of meshes could maintain their original wettability in harsh environments, and demonstrate high efficiency and recyclability for the separation of water/ oil mixtures containing boiling water, acid and salt. In addition, a T-shaped bidirectional device was assembled by fixing the two meshes with inverse wettability at the both horizontal ends of a T-tube, which can achieve continuous high-efficiency separation of various mixtures of water and oil regardless of their density relationship.

The mitochondrial import and assembly (MIA) pathway plays a vitally important role in import and oxidative folding of mitochondrial proteins. Erv1, a member of the FAD‐dependent Erv1/ALR disulphide bond generating enzyme family, is a key player of the MIA pathway. Although considerable progress has been made, the molecular mechanism of electron transfer within Erv1 is still not fully understood. The reduction potentials of the three redox centres were previously determined to be −320 mV for the shuttle disulphide, −150 mV for the active‐site disulphide and −215 mV for FAD cofactor. However, it is unknown why FAD of Erv1 has such a low potential compared with other sulfhydryl oxidases, and why the shuttle disulphide has a potential as low as many of the stable structural disulphides of the substrates of MIA pathway. In this study, the three reduction potentials of Erv1 were reassessed using the wild‐type and inactive mutants of Erv1 under anaerobic conditions. Our results show that the standard potentials for the shuttle and active‐site disulphides are approximately −250 mV and −215 ~ −260 mV, respectively, and the potential for FAD cofactor is −148 mV. Our results support a model that both disulphide bonds are redox‐active, and electron flow in Erv1 is thermodynamically favourable. Furthermore, the redox behaviour of Erv1 was confirmed, for the first time using Mia40, the physiological electron donor of Erv1. Together with previous studies on proteins of MIA pathway, we conclude that electron flow in the MIA pathway is a thermodynamically favourable, smoothly downhill process for all steps.DatabaseErv1: EC 1.8.3.2.