Chemoenzymatic Labeling, Detection and Profiling of Core Fucosylation in Live Cells.

Core fucosylation, the attachment of an α-1,6-linked-fucose to the N-glycan core pentasaccharide, is an abundant protein modification that plays critical roles in various biological processes such as cell signaling, B cell development, antibody-dependent cellular cytotoxicity, and oncogenesis. However, the tools currently used to detect core fucosylation suffer from poor specificity, exhibiting cross-reactivity against all types of fucosylation. Herein we report the development of a new chemoenzymatic strategy for the rapid and selective detection of core fucosylated glycans. This approach employs a galactosyltransferase enzyme identified fromCaenorhabditis elegansthat specifically transfers an azido-appended galactose residue onto core fucose via a ß-1,4 glycosidic linkage. We demonstrate that the approach exhibits superior specificity toward core fucose on a variety of complex N-glycans. The method enables detection of core fucosylated glycoproteins from complex cell lysates, as well as on live cell surfaces, and it can be integrated into a diagnostic platform to profile protein-specific core fucosylation levels. This chemoenzymatic labeling approach offers a new strategy for the identification of disease biomarkers and will allow researchers to further characterize the fundamental role of this important glycan in normal and disease physiology.

Linear oligo(phenylenevinylene)-based covalent organic frameworks.

Covalent organic frameworks (COFs) incorporating oligo(phenylenevinylene) units have shown promise in enhancing photocatalytic hydrogen evolution. This study presents a series of linear oligo(phenylenevinylene)-based COFs with various ratios of ß-ketoenamine to imine linkages. The COFs-950-OMe are crystalline, exhibiting higher surface area compared to amorphous COFs-950, due to the introduction of methoxy side groups.

A near-zero-discharge recirculating aquaculture system with 3D-printed poly (lactic acid) honeycomb as solid carbon.

A novel near-zero-discharge recirculating aquaculture system was successfully set up and ran for six months or above. A uniquely designed and 3D printed poly (lactic acid) (PLA) structure was applied as carbon source. The system achieved over 50 % daily nitrogen removal capability and maintained a low NO3-N level of <0.5 mg/L. Steady water quality was observed throughout the experiment period. Microbial distribution was studied and top abundant microorganisms and their general functions in carbon and nitrogen utilization were discussed. Denitrification and L-glutamate formation were identified as two main nitrogen pathways. The cooccurrence network connecting various genera and multiple functions was revealed. Subtilisin was one important PLA degrading enzymes in the system.

Mechanistic insight into the photoconversion of losartan potassium mediated by different types of microplastics.

Nowadays the proliferation of microplastics (MPs) in aquatic environments and impacts on the fate of organic contaminants (OCs) has drawn sustained worldwide attention. In this study, we investigated the effects of different types and aging degrees of MPs, specifically polystyrene (PSMPs), polyethylene terephthalate (PETMPs), and polylactic acid (PLAMPs), on the photo-transformation of LSTPs. Our results revealed that the facilitation of LSTP photoconversion by PSMPs exhibited a positive linear relationship with aging degree. On the other hand, the effects of PETMPs with different oxidation levels on LSTP photoconversion were weak, while the contribution of PLAMPs decreased as aging increased. Characterizations, quenching and probing experiments showed the aging mechanisms and the generation of reactive oxygen species (ROS) converged among various MPs. Specifically, theoretical calculations, TOC and GC-MS were conducted to verify that in the PLA0-mediated systems, it was the intermediates of PLA0 that prevailed in promoting the photoconversion of LSTP. The aged PLA own have a large propensity to consume ROS, which diminished their promotion of LSTP degradation. This differd from the reactions involving PSMPs and PETMPs, where the microplastic particles themselves were the main drivers of the photoconversion process rather than intermediates.

Site-specific N-glycoproteomic analysis reveals up-regulated fucosylation in seminal plasma of asthenozoospermia.

N-linked glycoproteins are rich in seminal plasma, playing essential roles in supporting sperm function and fertilization process. The alteration of seminal plasma glycans and its correspond glycoproteins may lead to sperm dysfunction and even infertility. In present study, an integrative analysis of glycoproteomic and proteomic was performed to investigate the changes of site-specific glycans and glycoptoteins in seminal plasma of asthenozoospermia. By large scale profiling and quantifying 5,018 intact N-glycopeptides in seminal plasma, we identified 92 intact N-glycopeptides from 34 glycoproteins changed in asthenozoospermia. Especially, fucosylated glycans containing lewis x, lewis y and core fucosylation were significantly up-regulated in asthenozoospermia compared to healthy donors. The up-regulation of fucosylated glycans in seminal plasma may interfere sperm surface compositions and regulation of immune response, which subsequently disrupts sperm function. Three differentiated expression of seminal vesicle-specific glycoproteins (fibronectin, seminogelin-2, and glycodelin) were also detected with fucosylation alteration in seminal plasma of asthenozoospermia. The interpretation of the altered site-specific glycan structures provides data for the diagnosis and etiology analysis of male infertility, as well as providing new insights into the potential therapeutic targets for male infertility.

Vibrational Spectra Simulations in Amino Acid-Based Imidazolium Ionic Liquids.

We present maximally localized Wannier functions and Voronoi tessellation to obtain dipole moment distributions for vibrational spectra in several important ionic liquids calculated by using ab initio molecular dynamics simulations. IR and Raman spectra of various imidazolium-based ionic liquids (ILs) paired with six amino acid anions are shown herein. For IR spectra, two approaches (Wannier and Voronoi) are in agreement with respect to the relative intensities and the overall shapes for the main peaks. Under Raman spectra, the polarizability of the covalent bonds is shown to affect the strength of the Raman scattering signal. The advantage of the Voronoi tessellation method, being that it does not have strong spikes in its time development, is demonstrated by the comparison of two theoretical methods (Wannier and Voronoi) with experimental data. We analyze the errors between theoretical and experimental spectroscopic data, with the Voronoi method shown to accurately reproduce experimental values. In addition, theoretical spectroscopy shows the ability to accurately separate components of a mixture. The combination of theoretical and experimental methods is utilized to understand the spectroscopic properties of amino acid-based imidazolium ILs.

Optoelectronically navigated nano-kirigami microrotors.

With the rapid development of micro/nanofabrication technologies, the concept of transformable kirigami has been applied for device fabrication in the microscopic world. However, most nano-kirigami structures and devices were typically fabricated or transformed at fixed positions and restricted to limited mechanical motion along a single axis due to their small sizes, which significantly limits their functionalities and applications. Here, we demonstrate the precise shaping and position control of nano-kirigami microrotors. Metallic microrotors with size of ~10 micrometers were deliberately released from the substrates and readily manipulated through the multimode actuation with controllable speed and direction using an advanced optoelectronic tweezers technique. The underlying mechanisms of versatile interactions between the microrotors and electric field are uncovered by theoretical modeling and systematic analysis. This work reports a novel methodology to fabricate and manipulate micro/nanorotors with well-designed and sophisticated kirigami morphologies, providing new solutions for future advanced optoelectronic micro/nanomachinery.

Oligo(phenylenevinylene)-Based Covalent Organic Frameworks with Kagome Lattice for Boosting Photocatalytic Hydrogen Evolution.

Covalent organic frameworks (COFs) have shown great advantages as photocatalysts for hydrogen evolution. However, the effect of linkage geometry and type of linkage on the extent of π-electron conjugation in the plane of the framework and photocatalytic properties of COFs remains a significant challenge. Herein, two Kagome (kgm) topologic oligo(phenylenevinylene)-based COFs are designed and synthesized for boosting photocatalytic hydrogen evolution via a "two in one" strategy. Under visible light irradiation, COF-954 with 5 wt% Pt as cocatalyst exhibits high hydrogen evolution rate (HER) of 137.23 mmol g-1 h-1 , outperforming most reported COF-based photocatalysts. More importantly, even in natural seawater, COF-954 shows an average HER of 191.70 mmol g-1 h-1 under ultraviolet-visible (UV-vis) light irradiation. Additionally, the water-drainage experiments indoors and outdoors demonstrate that 25 and 8 mL hydrogen gas could be produced in 80 min under UV-vis light and natural sunlight, respectively, corresponding to a high HER of 167.41 and 53.57 mmol h-1 g-1 . This work not only demonstrates an effective design strategy toward highly efficient COF-based photocatalysts, but also shows the great potential of using the COF-based photocatalysts for photocatalytic hydrogen evolution.

Enhanced degradation of chloramphenicol via heterogeneous activation of peroxymonosulfate by Fe3O4 and gallic acid.

In this study, we demonstrated the effective degradation of wide-spectrum antibiotic chloramphenicol (CAP) by Fe3O4/peroxymonosulfate (PMS) system modified by gallic acid (GA). GA/Fe3O4/PMS showed a substantially higher degradation rate (77.6%) than Fe3O4/PMS (8.3%). The active components were detected by electron spin-resonance spectroscopy (ESR) and the quenching experiments. The results showed that the hydroxyl radical (HO•) was the main reason for the degradation of CAP. In the GA/Fe3O4/PMS system, the trace amount of dissolved iron ion were not the main species that activated PMS. Surface characterization and theoretical simulations showed that Fe atoms on Fe3O4 were responsible for PMS activation rather than a homogenous reaction. Five probable CAP degradation pathways were identified by density functional theory (DFT) calculations and liquid-phase mass spectrometry. Finally, the reusability of Fe3O4 was measured, and the GA/Fe3O4/PMS system maintained high efficiency after 5 times applications. The total organic carbon (TOC) removal rate reached 46.5% after reacting for 12 h. The gallic acid effectively promotes the circulation of Fe(II)/Fe(III) on solid surfaces and enhanced the degradation capacity of the original system. The research proposed a new way of directly employing plant polyphenols to boost the degradation ability of contaminants in heterogeneous systems.

Locality in amino-acid based imidazolium ionic liquids.

Several amino-acid based imidazolium ILs are investigated through the use of ab initio molecular dynamics (AIMD), which includes full polarization. The electric dipole moment distribution and polarization is used as a means of characterizing and understanding these complex systems. Various charge scheme methods were analyzed (Wannier function, Blöchl, Löwdin and Mulliken charge schemes and Voronoi tessellation) to determine their ability to predict dipole moments. These results and the following comparison of methods further deepen the knowledge of polarization by highlighting the importance of the anion and cation separately on polarizability contribution and the need to select a suitable method to predict these. The angular probability distribution is utilized to measure the degree of locality in monopole-dipole electrostatic interactions, which showed no preferential alignment over 700 pm. In addition, the IR and Raman spectra from Voronoi tessellation of [C2C1Im][ala] were analyzed. In these, the strongest signalling peaks showed consistency with experiment and the ability to differentiate between anion and cation components of the IL.

Site-specific N-glycan changes during semen liquefaction.

Normal liquefaction of semen is one of the key steps to ensure the smooth progress of fertilization, and glycosylation has been reported to be involved in the whole process of fertilization. Till now, it is still unclear whether and how glycosylation changes during the liquefaction process of semen. In this study, by performing a glycoproteomic analysis of human semen with the liquefaction process (liquefaction time of semen: 0 min vs 30 min) using our recently developed StrucGP software combined with the Tandem Mass Tags (TMT) based quantification, we identified 25 intact glycopeptides (IGPs) from 10 glycoproteins in semen that were significantly changed during liquefaction, including 23 up-regulated and two down-regulated. Among the 23 up-regulated glycopeptides, half were modified with sialylated glycans, suggesting that sialylated glycans may play a key role in the semen liquefaction process. The data provide an invaluable resource for further studies on the role of glycosylation during semen liquefaction.

Multi-View Deep Gaussian Processes for Supervised Learning.

Multi-view learning is a widely studied topic in machine learning, which considers learning with multiple views of samples to improve the prediction performance. Even though some approaches have sprung up recently, it is still challenging to jointly explore information contained in different views. Multi-view deep Gaussian processes have shown strong advantages in unsupervised representation learning. However, they are limited when dealing with labeled multi-view data for supervised learning, and ignore the application potential of uncertainty estimation. In this paper, we propose a supervised multi-view deep Gaussian process model (named SupMvDGP), which uses the label of the views to further improve the performance, and takes the quantitative uncertainty estimation as a supplement to assist humans to make better use of prediction. According to the diversity of views, the SupMvDGP can establish asymmetric depth structure to better model different views, so as to make full use of the property of each view. We provide a variational inference method to effectively solve the complex model. Finally, we conduct comprehensive comparative experiments on multiple real world datasets to evaluate the performance of SupMvDGP. The experimental results show that the SupMvDGP achieves the state-of-the-art results in multiple tasks, which verifies the effectiveness and superiority of the proposed approach. Meanwhile, we provide a case study to show that the SupMvDGP has the ability to provide uncertainty estimation than alternative deep models, which can alert people to better treat the prediction results in high-risk applications.

Improved photocatalytic activity of TiO2 with a regulated covalent organic framework thin film.

In this work, one-dimensional TiO2 nanotube arrays are coupled with a covalent organic framework (COF) thin film with a controlled thickness to form a three-dimensional heterojunction, which exhibits a 3.3-fold higher hydrogen evolution rate than that of TiO2, and becomes active for CO2 conversion, compared to the bare COF. Such high activity results from the large difference in Fermi levels forming an internal electric field at the interface.

Maximal performance of intact N-glycopeptide enrichment using sequential HILIC and MAX columns.

Low abundance and heterogeneity of N-glycosylation at the peptide level poses a great challenge to the structural and functional analysis of glycosylation in the field of glycobiology. Solving this conundrum requires a sufficient and specific method for intact N-glycopeptide enrichment. Using the C18 or HLB desalting column followed by the mixed-mode strong anion exchange (MAX) or hydrophilic interaction chromatography (HILIC) glycopeptide enrichment column are commonly applied approaches for sample preparation of intact N-glycopeptides from complex samples. Herein, we compared the effects of different combinations of two desalting columns and two enrichment columns using equal amounts of mouse brain tissues from the same source. The results revealed the C18 column was a bit superior to the HLB column, and the MAX and HILIC columns were complementary on intact N-glycopeptides enrichment. Additionally, the results also demonstrated that enriching glycopeptides using a HILIC column followed by a MAX column from the flow-through solution got a better enrichment performance than the reversed order. Based on these results, the sequential enrichment of glycopeptides using HILIC and then MAX columns could maximize the enrichment performance of intact N-glycopeptides, and therefore is an option for in-depth analysis of site-specific glycoproteome.

Partial Multiview Representation Learning With Cross-View Generation.

Multiview learning has made significant progress in recent years. However, an implicit assumption is that multiview data are complete, which is often contrary to practical applications. Due to human or data acquisition equipment errors, what we actually get is partial multiview data, which existing multiview algorithms are limited to processing. Modeling complex dependencies between views in terms of consistency and complementarity remains challenging, especially in partial multiview data scenarios. To address the above issues, this article proposes a deep Gaussian cross-view generation model (named PMvCG), which aims to model views according to the principles of consistency and complementarity and eventually learn the comprehensive representation of partial multiview data. PMvCG can discover cross-view associations by learning view-sharing and view-specific features of different views in the representation space. The missing views can be reconstructed and are applied in turn to further optimize the model. The estimated uncertainty in the model is also considered and integrated into the representation to improve the performance. We design a variational inference and iterative optimization algorithm to solve PMvCG effectively. We conduct comprehensive experiments on multiple real-world datasets to validate the performance of PMvCG. We compare the PMvCG with various methods by applying the learned representation to clustering and classification. We also provide more insightful analysis to explore the PMvCG, such as convergence analysis, parameter sensitivity analysis, and the effect of uncertainty in the representation. The experimental results indicate that PMvCG obtains promising results and surpasses other comparative methods under different experimental settings.

A strain-reinforcing elastomer adhesive with superior adhesive strength and toughness.

Strong and ductile adhesives often undergo both interfacial and cohesive failure during the debonding process. Herein, we report a rare self-reinforcing polyurethane adhesive that shows the different phenomenon of only interfacial failure yet still exhibiting superior adhesive strength and toughness. It is synthesized by designing a hanging adhesive moiety, hierarchical H-bond moieties, and a crystallizable soft segment into one macromolecular polyurethane. The former hanging adhesive moiety allows the hot-melt adhesive to effectively associate with the target substrate, providing sufficient adhesion energy; the latter hierarchical H-bond moieties and a crystallizable soft segment cooperate to enable the adhesive to undergo large lap-shear deformations through sacrificing weak bonds and mechano-responsive strength through the fundamental mechanism of strain-induced crystallization. As a result, this polyurethane adhesive can keep itself intact during the debonding process while still withstanding a high lap-shear strength and dissipating tremendous stress energy. Its adhesive strength and work of debonding are as high as 11.37 MPa and 10.32 kN m-1, respectively, outperforming most reported tough adhesives. This self-reinforcing adhesive is regarded as a new member of the family of strong and ductile adhesives, which will provide innovative chemical and structural inspirations for future conveniently detachable yet high-performance adhesives.

Quantitative probing of reactive oxygen species and their selective degradation on contaminants in peroxymonosulfate-based process enhanced by picolinic acid.

The processes of Fe(III) activated peroxymonosulfate (PMS) in degrading contaminants have been extensively studied. Herein, a biodegradable chelating agent, picolinic acid (PICA), was introduced to the PMS/Fe(III) process to improve the reaction efficiency. The emphases of this study were placed on the quantification of steady-state concentrations of reactive oxygen species (ROS). Experiments presented that five types of ROS, including Fe(IV), SO4•-, HO•, 1O2 and O2•- coexisted in this system. Four typical probe compounds were used to quantify the steady-state concentration of ROS under different variables. The steady-state concentration of Fe(IV) ([Fe(IV)]ss) was 3-5 orders of magnitude higher than that of other ROS, followed by 1O2 and SO4•-, whereas HO• had the lowest concentration. The reaction between PMS and PICA was first explored in our study and results showed that 1O2 and O2•- would form in this reaction. Owing to the hybrid oxidation by multiple ROS, this system showed high oxidation capacity, and could effectively degrade a variety of pollutants. The contributions of ROS to the alleviation of pollutants varied depending on their concentrations and specific reactivity of substrates. Generally, organic contaminants with phenol structures were prone to react with Fe(IV). Overall, this study compared the steady-state concentrations of different ROS and revealed the intrinsic ROS formation mechanisms.

Using bioinformatics and systems biology methods to identify the mechanism of interaction between COVID-19 and nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is considered a risk factor for severe COVID-19, but the mechanism remains unknown. This study used bioinformatics to help define the relationship between these diseases. The GSE147507 (COVID-19), GSE126848 (NAFLD), and GSE63067 (NAFLD-2) datasets were screened using the Gene Expression Omnibus. Common differentially expressed genes were then identified using a Venn diagram. Gene ontology analysis and KEGG pathway enrichment were performed on the differentially expressed genes. A protein-protein interaction network was also constructed using the STRING platform, and key genes were identified using the Cytoscape plugin. GES63067 was selected for validation of the results. Analysis of ferroptosis gene expression during the development of the 2 diseases and prediction of their upstream miRNAs and lncRNAs. In addition, transcription factors (TFs) and miRNAs related to key genes were identified. Effective drugs that act on target genes were found in the DSigDB. The GSE147507 and GSE126848 datasets were crossed to obtain 28 co-regulated genes, 22 gene ontology terms, 3 KEGG pathways, and 10 key genes. NAFLD may affect COVID-19 progression through immune function and inflammatory signaling pathways. CYBB was predicted to be a differential ferroptosis gene associated with 2 diseases, and the CYBB-hsa-miR-196a/b-5p-TUG1 regulatory axis was identified. TF-gene interactions and TF-miRNA coregulatory network were constructed successfully. A total of 10 drugs, (such as Eckol, sulfinpyrazone, and phenylbutazone) were considered as target drugs for Patients with COVID-19 and NAFLD. This study identified key gene and defined molecular mechanisms associated with the progression of COVID-19 and NAFLD. COVID-19 and NAFLD progression may regulate ferroptosis through the CYBB-hsa-miR-196a/b-5p-TUG1 axis. This study provides additional drug options for the treatment of COVID-19 combined with NAFLD disease.

Intermediate Formation of Macrocycles for Efficient Crystallization of 2D Covalent Organic Frameworks with Enhanced Photocatalytic Hydrogen Evolution.

Covalent organic frameworks (COFs) have gained significant attention as key photocatalysts for efficient solar light conversion into hydrogen production. Unfortunately, the harsh synthetic conditions and intricate growth process required to obtain highly crystalline COFs greatly hinder their practical application. Herein, we report a simple strategy for the efficient crystallization of 2D COFs based on the intermediate formation of hexagonal macrocycles. Mechanistic investigation suggests that the use of 2,4,6-triformyl resorcinol (TFR) as the asymmetrical aldehyde build block allows the equilibration between irreversible enol-to-keto tautomerization and dynamic imine bonds to produce the hexagonal ß-ketoenamine-linked macrocycles, the formation of which could provide COFs with high crystallinity in half hour. We show that COF-935 with 3 wt % Pt as cocatalyst exhibit a high hydrogen evolution rate of 67.55 mmol g-1 h-1 for water splitting when exposed to visible light. More importantly, COF-935 exhibits an average hydrogen evolution rate of 19.80 mmol g-1 h-1 even at a low loading of only 0.1 wt % Pt, which is a significant breakthrough in this field. This strategy would provide valuable insights into the design of highly crystalline COFs as efficient organic semiconductor photocatalysts.

A comparative study on Fe(III)/H2O2 and Fe(III)/S2O82- systems modified by catechin for the degradation of atenolol.

The processes of Fe(III) activated persulfate (PS) and H2O2 modified by catechin (CAT) had been shown to be effective in degrading contaminants. In this study, the performance, mechanism, degradation pathways and products toxicity of PS (Fe(III)/PS/CAT) and H2O2 (Fe(III)/H2O2/CAT) systems were compared using atenolol (ATL) as a model contaminant. 91.0% of ATL degradation was reached after 60 min in H2O2 system which was much higher than that in PS system (52.4%) under the same experimental condition. CAT could react directly with H2O2 to produce small amounts of HO• and the degradation efficiency of ATL was proportional to CAT concentration in H2O2 system. However, the optimal CAT concentration was 5 µM in PS system. The performance of H2O2 system was more susceptible to pH than that of PS system. Quenching experiments were conducted indicating that SO4•- and HO• were produced in PS system while HO• and O2•- accounted for ATL degradation in H2O2 system. Seven pathways with nine byproducts and eight pathways with twelve byproducts were put forward in PS and H2O2 systems respectively. Toxicity experiments showed that the inhibition rates of luminescent bacteria were both decreased about 25% after 60 min reaction in two systems. Although the software simulation result showed few intermediate products of both systems were More toxic than ATL, but the amounts of them were 1-2 orders of magnitude lower than ATL. Moreover, the mineralization rates were 16.4% and 19.0% in PS and H2O2 systems respectively.