14 results about "Glucan synthesis" patented technology

The application belongs to the technical field of biological gene engineering, and particularly relates to a barley HvCslf6 promoter element and application thereof in regulating the content of barley grain beta-glucan, wherein the barley HvCslf6 promoter element is located at 295bp-300bp upstream of a transcription start site of a barley HvCslf6 gene; the nucleotide sequence of the HvCslf6 promoter element is CCGTTG, and the HvCslf6 promoter element belongs to a CCAAT-box element; the gene number of the HvCslf6 gene in BARLEX Morex v3 Gene Models is HORVU.MOREX.r3.7HG0698110. The application finds a key element which can affect the content of beta-glucan in barley grains in the upstream promoter region of a main effect gene HvCslf6 of barley beta-glucan synthesis by using a gene editing technology, and thus provides a method capable of preparing transgenic plants with changed content of beta-glucan in barley grains, and provides a new means and tool for detecting and regulating the content of beta-glucan in barley grains.

The invention discloses an application of a phellinus igniarius gene in beta-glucan synthesis. According to the invention, a key gene evm.TU.contig16.116 participating in phellinus igniarius beta-glucan synthesis is obtained by cloning from phellinus igniarius for the first time. By constructing the recombinant phellinus igniarius strain of the overexpressed evm.TU.contig16.116 gene, the yield of the phellinus igniarius beta-glucan and the yield of the phellinus igniarius crude polysaccharide are remarkably increased. Experiments prove that the extracellular crude polysaccharide yield and the intracellular crude polysaccharide yield of the recombinant phellinus igniarius strain are greatly increased compared with those of a control strain, and the obtained phellinus igniarius beta-glucan has better antioxidant activity. The invention provides a theoretical basis for improving biosynthesis of phellinus igniarius beta-glucan by utilizing a genetic engineering technical means.

This invention belongs to the field of microbial fermentation technology and discloses a method and application for improving the production of staminodesmotic acid (Sclerotium sclerotiorum) based on dynamic osmotic pressure regulation. The method uses *Sclerotium sclerotiorum* as the production strain and employs a synergistic strategy of initial culture medium component optimization, precise osmotic pressure regulation during fermentation, and dynamic feeding to enhance synthesis. Utilizing the dual characteristics of sucrose as a carbon source and osmotic pressure regulator, and the osmotic pressure regulating effect of KCl, the osmotic pressure during fermentation is precisely controlled between 1050-1300 mOsmol / kg. This activates the MAPK-CWI signaling pathway and FKs2 gene expression, directionally promoting staminodesmotic acid synthesis and increasing staminodesmotic acid yield. This invention, by optimizing the initial carbon source and inorganic salt concentration, precisely regulating osmotic pressure during fermentation through feeding, and combining molecular mechanism analysis, achieves a significant increase in staminodesmotic acid yield, reduces industrial production costs, and provides technical support for the large-scale industrial production of staminodesmotic acid.

This application relates to the field of biotechnology, specifically disclosing a *Pichia pastoris* yeast, its construction method, and its applications. This application involves knocking out the *gas1* gene, which is related to β-glucan synthesis, in *Pichia pastoris*. By deleting the *gas1* gene, which encodes β-glucan in the cell wall of *Pichia pastoris*, this application reduces cell size, decreases the transfer distance from the cell surface to the nucleus, improves oxygen transfer and product secretion during high-density culture, and enhances fermentation efficiency. Furthermore, the *Pichia pastoris* yeast constructed using this application enhances the synthesis of the intracellular product bisabolol and also enhances its secretion capacity. This application, by reducing cell size and decreasing the carbon flow to cell wall polysaccharide synthesis while increasing the carbon source flow to target product synthesis, has significant implications for industrial production.

The present disclosure provides the use of β-1,3-glucan synthase like 5 (GSL5) for the improvement of the clubroot resistance in cruciferous crops as well as related products development, belonging to the area of molecular engineering for plant breeding. GSL5 gene is highly conserved in cruciferous plants and mutation of GSL5 can confer a broad-spectrum and high clubroot resistance to the cruciferous crops, demonstrating that molecular engineering of GSL5 can achieve the improvement of the clubroot resistance in cruciferous crops. The present disclosure provides a key gene and techniques for the improvement of the clubroot disease resistance and durable prevention and control of the clubroot disease in cruciferous crops.

This invention discloses an antimicrobial peptide, its pharmaceutical composition, and its applications. The invention optimizes the structure of the antimicrobial peptide through deuteration modification technology, significantly enhancing its targeted binding ability to β-1,3-D-glucan synthase. The affinity of this antimicrobial peptide for the aforementioned target is 9-27 times that of the control peptide. In vitro assays show that its minimum inhibitory concentration (MIC) against nine standard Candida strains is consistently 0.002 μg / mL, exhibiting significantly superior activity compared to fluconazole, anidoxurine, and the control peptide. It also exhibits extremely low cytotoxicity against L02 human normal hepatocytes. In in vivo experiments, in a neutropenic mouse model of Candida albicans infection, the antimicrobial peptide at all doses showed superior reduction in renal fungal load compared to anidoxurine and the control peptide. The antimicrobial peptide of this invention combines highly efficient anti-Candida activity, low cytotoxicity, and excellent in vivo efficacy, providing a safe and effective candidate drug for the treatment of drug-resistant candidiasis and possessing good clinical translational value.

The application specifically relates to a method for preparing glutathione by immobilized enzyme and application. The method for preparing glutathione provided by the application comprises synthesizing glutathione by using saccharomyces cerevisiae haploid ascospores as a fixed enzyme catalyst to catalyze substrate reaction, using an ATP in-situ regeneration reaction system of phosphoenolpyruvate as an energy supply system, the saccharomyces cerevisiae haploid ascospores are knocked out or inactivated in combination of one or more than two of cell wall beta-glucan synthesis genes, and GSH1 genes, GSH2 genes and PYK1 genes are co-expressed. The saccharomyces cerevisiae haploid ascospores for simultaneously producing GSH1, GSH2 and pyruvate kinase are used as a fixed enzyme catalyst to catalyze synthesis of glutathione, three enzymes no longer need to be added externally, raw material cost is greatly reduced, the obtained product is easy to purify, and the prepared glutathione is high in purity.

The invention discloses a ganoderma lucidum strain with high beta-glucan content and application thereof, a ganoderma lucidum mutant strain 106 is obtained by screening through an ARTP mutagenesis technology, the beta-glucan content in mycelium of the ganoderma lucidum mutant strain 106 reaches 14.4 mg / g fresh weight, and the technical bottleneck that the beta-glucan content of an existing ganoderma lucidum strain is low is solved. Six beta-glucan synthesis key genes (SEQ ID NO: 1-6) are identified through RNA-Seq sequencing, and a clear molecular target is provided for the subsequent directional improvement of the ganoderma lucidum beta-glucan synthesis capability through a metabolic engineering or gene editing technology.

The invention relates to the field of plant genetic engineering, in particular to application of an MYB transcription factor gene HvPHL2 in regulating and controlling the content of beta-glucan in barley grains. The MYB transcription factor gene HvPHL2 participating in regulation and control of the barley grain beta-glucan content is found, and through construction experiments of yeast single impurity, gel migration, dual luciferase and overexpression genetic materials, it is proved that the transcription factor HvPHL2 can be combined to CCAAT-box of a promoter region of a barley grain beta-glucan synthesis major gene HvCslf6, expression of an HvCslf6 promoter is inhibited, and the content of the barley grain beta-glucan in the barley grain beta-glucan synthesis major gene HvCslf6 in the barley grain beta-glucan synthesis major gene HvCslf6 in the barley grain beta-glucan synthesis major gene HvCslf6 is regulated and controlled. The method plays a key role in regulation and control of beta-glucan synthesis, and provides a new theoretical basis for genetic regulation and control of the beta-glucan content of the barley grains.

A method for hydrolyzing an alpha-1,5 glucosyl-fructose bond in a levansucrose, e.g., a sucrose, is disclosed. The method comprises contacting the sucrose with an alpha-glucosidase, e.g., a transglucosidase or a glucoamylase, under suitable conditions, during which the enzyme hydrolyzes at least one alpha-1,5 glucosyl-fructose bond of the sucrose. The method is used, e.g., to reduce the amount of levansucrose in a filtrate isolated from a glucan synthesis reaction.

The invention discloses an antibacterial peptide as well as a pharmaceutical composition and application thereof. The structure of the antibacterial peptide is optimized through a deuterated modification technology, and the targeted binding capacity of the antibacterial peptide to beta-1, 3-D-glucan synthetase is remarkably improved. The affinity of the antibacterial peptide to the target spot is 9-27 times that of a control peptide; in-vitro determination shows that the minimum inhibitory concentration (MIC) of the compound to nine standard candida strains is stabilized to be 0.002 mu g / mL, and the activity of the compound is remarkably superior to that of fluconazole, anidulafungin and control peptide; the cytotoxicity to L02 human normal hepatocytes is extremely low; in an in-vivo experiment, in a neutrophile granulocyte reduction mouse Candida albicans infection model, the kidney fungal load reduction effect under each dose of the antibacterial peptide is better than that of anidulafungin and a control peptide. The antibacterial peptide has efficient anti-candida activity, low cytotoxicity and excellent in-vivo curative effect, provides a safe and effective candidate drug for treatment of drug-resistant candidiasis, and has good clinical transformation value.

The invention discloses application of a CmGel4 gene in regulating and controlling the branching degree of beta-glucan of cordyceps militaris, and belongs to the technical field of bioengineering and genetic breeding of edible fungi. According to the invention, two recombinant cordyceps militaris strains, namely a cordyceps militaris CmGel4 overexpression strain and a cordyceps militaris CmGel4 key structural domain knockout strain, are constructed; according to the recombinant cordyceps militaris strain, accurate knockout of the beta-1, 3-glucanyl transferase gene CmGel4 in a cordyceps militaris genome and targeted insertion of a safety site CmSh1 are achieved, after fermentation is conducted for 6 days, the beta-glucan branching degree is increased by 5%-20%, the beta-glucan branching degree is reduced by 2%-16%, and the recombinant cordyceps militaris strain has good application in regulation and control of the beta-glucan branching degree of cordyceps militaris. According to the invention, the synthesis mechanism of edible and medicinal fungus polysaccharide can be understood from the molecular level, and a technical scheme is provided for modifying a glucan synthesis route of edible and medicinal fungi by using a gene editing technology.

The present application relates to the technical field of biological medicine, in particular to an antifungal drug composition based on (1,3)-beta-D-glucan synthase inhibitor and application thereof. In vivo and in vitro experiments prove that the combination of endogenous antibacterial peptide LL-37 and (1,3)-beta-D-glucan synthase inhibitor (such as caspofungin, micafungin, anidulafungin, rezafungin and albaconazole) shows significant synergistic inhibitory effect on multiple drug-resistant pathogenic fungi such as Candida albicans and Candida auris. Since free antibacterial peptides are easily degraded by proteases, the present application is based on the synergistic killing mechanism of breaking the network barrier of fungal cell wall and assisting endogenous defense peptide to target cell membrane, and ingeniously uses the "antibacterial peptide LL-37 expression promoter" to actively up-regulate the synthesis of host natural peptides, which provides a new drug regimen for clinical treatment of deep fungal infection.

Eufumafungin derivative triterpenoid antifungal compounds are used to treat and / or prevent Pneumocystis pneumonia (PCP) due to their unexpected efficacy against Pneumocystis spp. including their ability to reduce the lung burden of cyst and trophic forms of this fungi. The enfumafungin derivative triterpenoids (or pharmaceutically acceptable salts or hydrates thereof) are inhibitors of (1,3)-β-D-glucan synthesis and are useful in the treatment and / or prevention of PCP since they demonstrate potent activity against Pneumocystis spp. in in vivo models, exhibit adequate tissue penetration into lungs, and are well tolerated.