The Functional Characterization of an AA10 Lytic Polysaccharide Monooxygenase from 2-40 for Enhanced Chitin Biodegradation.

Lytic polysaccharide monooxygenases (LPMOs) represent copper-dependent enzymes pivotal in breaking down resilient polysaccharides like cellulose and chitin by means of oxidation, creating more accessible sites for glycoside hydrolases. To elevate the conversion efficiency of chitin, an AA10 LPMO was identified from the genome of 2-40 and heterologously expressed. The optimal pH for the activity of recombinant LPMO10A is 9.

Poly-β-D-(1,6)-N-acetyl-glucosamine (PNAG) glycan vaccines with broad spectrum neutralizing activities.

The development of bacterial vaccines is a complex challenge due to the substantial serological diversity of protective antigens. One promising antigenic target is the conserved surface polysaccharide poly-β-(1,6)-N-acetyl-D-glucosamine (PNAG). Despite its widespread distribution, antibodies raised against PNAG have shown restricted efficacy in promoting microbial elimination in vitro and safeguarding against infections in vivo.

Chemical and Enzymatic Synthesis of DisialylGb5 and Other Sialosides for Glycan Array Assembly and Evaluation of Siglec-Mediated Immune Checkpoint Inhibition.

Aberrant glycosylation, especially sialylation, on cell surface is often associated with cancer progression and immunosuppression. Over-sialylation of stage-specific embryonic antigen-4 (SSEA-4) to generate disialylGb5 (DSGb5) was reported to trigger Siglec-7 recognition and suppress NK-mediated target killing. In this study, efficient chemo-enzymatic and programmable one-pot methods were explored for the synthesis of DSGb5 and related sialosides for assembly of glycan microarrays and evaluation of binding specificity toward Siglecs-7, 9, 10, and 15 associated with immune checkpoint inhibition.

Discovery and biological evaluation of potent 2-trifluoromethyl acrylamide warhead-containing inhibitors of protein disulfide isomerase.

Protein disulfide isomerase (PDI) regulates multiple protein functions by catalyzing the oxidation, reduction, and isomerization of disulfide bonds. The enzyme is considered a potential target for treating thrombosis. We previously developed a potent PDI inhibitor, CPD, which contains the propiolamide as a warhead targeting cysteine residue in PDI.

Is the gene involved in the accumulation of (1,3;1,4)-β-D-glucan in wheats, their wild relatives and their hybrids?

Mixed linkage (1,3;1,4)-β-d-glucan (MLG) is a well-recognized bioactive carbohydrate and dietary fibre with expanding applications in food industry. The MLG are small components of the cell wall of vegetative tissues of cereals synthetized by members of the genes (). Within the family, the has been the major contributor in wheat.

Dynamic changes in the metabolome and microbiome during Citrus depressa Hayata liquid fermentation.

Citri Reticulatae Pericarpium (CRP) is a common traditional Chinese herbal medicine, valued for its multi-bioactivity. However, its processing time, environment, and microorganisms all affect its quality and bioactivity. To address this, the study replaced solid-state fermentation with liquid fermentation using microorganisms and isolated Bacillus amyloliquefaciens, respectively.

Inequality relations for NMR-based polymer homoblock analysis and extended application: Reanalysis of historical data on alginates, chitosans, homogalacturonans, and galactomannans.

There has been a long-standing bottleneck in the quantitative analysis of the frequencies of homoblock polyads beyond triads using H and C NMR for linear polysaccharides, primarily because monosaccharides within a long homoblock share similar chemical environments due to identical neighboring units, resulting in indistinct NMR peaks. In this study, through rigorous mathematical induction, inequality relations were established that enabled the calculation of frequency ranges of homoblock polyads from historically reported NMR-derived frequency values of diads and/or triads of alginates, chitosans, homogalacturonans, and galactomannans. The calculated homoblock frequency ranges were then applied to evaluate three chain growth statistical models, including the Bernoulli chain, first-order Markov chain, and second-order Markov chain, for predicting homoblock frequencies in these polysaccharides.

Production of therapeutic glycoproteins in glycoengineered plant: old farm for new crops.

Plant-based expression systems have emerged as promising avenues for the production of recombinant N-linked glycoproteins. This review offers insights into the evolution and progress of plant glycoengineering. It delves into the distinctive features of plant-derived N-glycans, the diverse range of plant hosts employed for glycoprotein synthesis, and the advancements in glycoengineering strategies aimed at generating glycoproteins with N-glycan structures akin to those produced in mammalian cell lines.

Substrate Specificities of Variants of Barley (1,3)- and (1,3;1,4)-β-d-Glucanases Resulting from Mutagenesis and Segment Hybridization.

Barley (1,3;1,4)-β-d-glucanase is believed to have evolved from an ancestral monocotyledon (1,3)-β-d-glucanase, enabling the hydrolysis of (1,3;1,4)-β-d-glucans in the cell walls of leaves and germinating grains. In the present study, we investigated the substrate specificities of variants of the barley enzymes (1,3;1,4)-β-d-glucan endohydrolase [(1,3;1,4)-β-d-glucanase] isoenzyme EII (EII) and (1,3)-β-d-glucan endohydrolase [(1,3)-β-d-glucanase] isoenzyme GII (GII) obtained by protein segment hybridization and site-directed mutagenesis. Using protein segment hybridization, we obtained three variants of EII in which the substrate specificity was that of a (1,3)-β-d-glucanase and one variant that hydrolyzed both (1,3)-β-d-glucans and (1,3;1,4)-β-d-glucans; the wild-type enzyme hydrolyzed only (1,3;1,4)-β-d-glucans.

Polymethoxyflavone from Citrus depressa as an inhibitor against various variants of SARS-CoV-2 spike protein.

Ethnopharmacological Relevance: In traditional Taiwanese medicine, Citrus depressa Hayata serves as the raw material of Chen-Pi which has been widely used to treat respiratory ailments. Scientific investigations have validated the attributes of C. depressa, elucidating its valuable properties, including antioxidative, anti-inflammatory, anticancer, neuroprotion, hepatoprotection, and hypolipidemic effects.

Machine learning-based monosaccharide profiling for tissue-specific classification of Wolfiporia extensa samples.

Machine learning (ML) has been used for many clinical decision-making processes and diagnostic procedures in bioinformatics applications. We examined eight algorithms, including linear discriminant analysis (LDA), logistic regression (LR), k-nearest neighbor (KNN), random forest (RF), gradient boosting machine (GBM), support vector machine (SVM), Naïve Bayes classifier (NB), and artificial neural network (ANN) models, to evaluate their classification and prediction capabilities for four tissue types in Wolfiporia extensa using their monosaccharide composition profiles. All 8 ML-based models were assessed as exemplary models with AUC exceeding 0.

The Gram-positive bacterium Romboutsia ilealis harbors a polysaccharide synthase that can produce (1,3;1,4)-β-D-glucans.

(1,3;1,4)-β-D-Glucans are widely distributed in the cell walls of grasses (family Poaceae) and closely related families, as well as some other vascular plants. Additionally, they have been found in other organisms, including fungi, lichens, brown algae, charophycean green algae, and the bacterium Sinorhizobium meliloti. Only three members of the Cellulose Synthase-Like (CSL) genes in the families CSLF, CSLH, and CSLJ are implicated in (1,3;1,4)-β-D-glucan biosynthesis in grasses.

Current insights of factors interfering the stability of lytic polysaccharide monooxygenases.

Cellulose and chitin are two of the most abundant biopolymers in nature, but they cannot be effectively utilized in industry due to their recalcitrance. This limitation was overcome by the advent of lytic polysaccharide monooxygenases (LPMOs), which promote the disruption of biopolymers through oxidative mechanism and provide a breakthrough in the action of hydrolytic enzymes. In the application of LPMOs to biomass degradation, the key to consistent and effective functioning lies in their stability.

Multivalent Carbohydrate Nanocomposites for Tumor Microenvironment Remodeling to Enhance Antitumor Immunity.

Current cancer immunotherapeutic strategies mainly focus on remodeling the tumor microenvironment (TME) to make it favorable for antitumor immunity. Increasing attention has been paid to developing innovative immunomodulatory adjuvants that can restore weakened antitumor immunity by conferring immunogenicity to inflamed tumor tissues. Here, a galactan-enriched nanocomposite (Gal-NC) is developed from native carbohydrate structures through an optimized enzymatic transformation for effective, stable, and biosafe innate immunomodulation.

Design, structure-activity relationships, and enzyme kinetic studies of tricyclic and tetracyclic coumarin-based sulfamates as steroid sulfatase inhibitors.

Inhibition of steroid sulfatase (STS) decreases estrogen production and thus, suppresses tumor proliferation. Inspired by irosustat, the first STS inhibitor in clinical trials, we explored twenty-one tricyclic and tetra-heterocyclic coumarin-based derivatives. Their STS enzyme kinetic parameters, docking models, and cytotoxicity toward breast cancer and normal cells were evaluated.

Effective Organotin-Mediated Regioselective Functionalization of Unprotected Carbohydrates.

Regioselective functionalization of unprotected carbohydrates at a secondary OH group in the presence of primary OH groups based on the commonly used organotin-mediated reaction has been improved. We found that the preactivation of the dibutylstannylene acetal intermediate with tetrabutylammonium bromide in toluene is a key to the improved condition for the efficient, high-yielding, and regioselective tosylation, benzoylation, or benzylation of unprotected carbohydrates. The counteranion of tetrabutylammonium ion with a weak coordination ability plays a crucial role in the improved regioselective reactions.

Structures of the xyloglucans in the monocotyledon family Araceae (aroids).

The xyloglucans of all aquatic Araceae species examined had unusual structures compared with those of other non-commelinid monocotyledon families previously examined. The aquatic Araceae species Lemna minor was earlier shown to have xyloglucans with a different structure from the fucogalactoxyloglucans of other non-commelinid monocotyledons. We investigated 26 Araceae species (including L.

The Design, Structure-Activity, and kinetic studies of 3-Benzyl-5-oxa-1,2,3,4-Tetrahydro-2H-chromeno-(3,4-c)pyridin-8-yl sulfamates as Steroid sulfatase inhibitors.

Steroid sulfatase inhibitors block the local production of estrogenic steroids and are attractive agents for the treatment of estrogen-dependent cancers. Inspiration of coumarin-based inhibitors, we synthesized thirty-two 5-oxa-1,2,3,4-tetrahydro-2H-chromeno-(3,4-c)pyridin-8-yl sulfamates, focusing on the substitution derivatives on the adjacent phenyl ring and evaluated their abilities to block STS from human placenta and MCF-7 cells. SAR analysis revealed that the incorporation of chlorine at either meta and/or para position of the adjacent phenyl ring of the tricyclic skeleton enhanced STS inhibition.