β-1,3-Glucans form the major carbohydrate component of fungal cell walls, playing a vital role in cell viability, stress response, virulence, and even healthy functions such as immuno-enhancement. The elongation and branching of β-1,3-glucans is a mystery. More evidence proved the β-1, 3-glucantransferases belonging to GH72 or GH17 family to branch and remodel the synthesized linear β-1, 3-glucan chain by cleaving its internal β-1, 3-linkage and transfer the cleaved fragment to the nonreducing end of another β-1, 3-glucan acceptor.
View Article and Find Full Text PDFOxalate decarboxylase converts oxalate to formate and CO without requiring organic cofactors, making it biotechnologically relevant for applications in food, agriculture, and diagnostics. Its activity is highly dependent on pH; however, the pH-dependent catalytic mechanism remains poorly understood. This study identified a novel oxalate decarboxylase, BsOxdC, from Bacillus safensis and investigated its catalytic properties through heterologous expression and enzymatic assays.
View Article and Find Full Text PDFGenus bacteria mainly consume glucose through the Entner-Doudoroff (ED) route due to a lack of a functional Embden-Meyerhof-Parnas (EMP) pathway. In the present study, a 6-phosphogluconate dehydratase () operon in the ED route was well investigated to find its structural characteristics and roles in the regulation of glucose consumption and 2-ketogluconic acid (2KGA) metabolism in the industrial 2KGA-producer JUIM01. The operon contained four structural genes of , , , and , encoding 6-PG dehydratase Edd, glucokinase Glk, response regulatory factor GltR, and histidine kinase GtrS, respectively.
View Article and Find Full Text PDFEdible mushrooms are an important food source with high nutritional and medicinal value. They are a useful source for studying phylogenetic evolution and species divergence. The exploration of the evolutionary relationships among these species conventionally involves analyzing sequence variations within their complete mitochondrial genomes, which range from 31,854 bp (Cordyceps militaris) to 197,486 bp (Grifolia frondosa).
View Article and Find Full Text PDFThe design of novel electrode deflector structures (EDSs) introduced a promising strategy for enhancing raceway ponds performance, increasing carbon fixation, and improving microalgal biomass accumulation. The computational fluid dynamics, based flow field principles, proved that the potency of arc-shaped electrode deflector structures (A-EDS) and spiral electrode deflector structures (S-EDS) were optimal. These configurations yielded superior culture effects, notably reducing dead zones by 9.
View Article and Find Full Text PDFCrit Rev Biotechnol
November 2024
Fungal α/β-glucans have significant importance in cellular functions including cell wall structure, host-pathogen interactions and energy storage, and wide application in high-profile fields, including food, nutrition, and pharmaceuticals. Fungal species and their growth/developmental stages result in a diversity of glucan contents, structures and bioactivities. Substantial progresses have been made to elucidate the fine structures and functions, and reveal the potential molecular synthesis pathway of fungal α/β-glucans.
View Article and Find Full Text PDFPolysaccharides are the main polymers in edible fungi Grifola frondosa, playing a crucial role in the physiology and representing the healthy benefits for humans. Recent efforts have well elucidated the fine structures and biological functions of G. frondosa polysaccharides.
View Article and Find Full Text PDFBackground: Grifola frondosa is a Basidiomycete fungus belonging to the family of Grifolaceae and the order of Polyporales. β-Glucans are the main polymers in G. frondosa, playing a crucial role in the physiology and representing the healthy benefits for humans.
View Article and Find Full Text PDFβ-1,3-Glucan synthases play key roles in glucan synthesis, cell wall assembly, and growth of fungi. However, their multi-transmembrane domains (over 14 TMHs) and large molecular masses (over 100 kDa) significantly hamper understanding of their catalytic characteristics and mechanisms. In the present study, the 5841-bp gene encoding the 221.
View Article and Find Full Text PDFGlobally, the release of acrylonitrile-butadienestyrene (ABS) wastewater from numerous industries is a serious concern. Recently, oil-rich filamentous algae Tribonema sp has been grown utilizing toxic but nutrient-rich ABS effluent. Here, Tribonema sp.
View Article and Find Full Text PDFMicrobial oils have gained massive attention because of their significant role in industrial applications. Currently plants and animals are the chief sources of medically and nutritionally important fatty acids. However, the ever-increasing global demand for polyunsaturated fatty acids (PUFAs) cannot be met by the existing sources.
View Article and Find Full Text PDFThis study attempted to remove acrylonitrile and acetophenone from simulated acrylonitrile butadiene styrene (ABS) based wastewater while recovering nitrogen and phosphorus using the carbohydrate-rich filamentous microalgae Tribonema sp.. Results showed that typical acetophenone and acrylonitrile presented significant inhibitory effect on Tribonema sp.
View Article and Find Full Text PDFβ-1,3-Glucans are well-known biological and health-promoting compounds in edible fungi. Our previous results characterized a glucan synthase gene (GFGLS) of Grifola frondosa for the first time to understand its role in mycelial growth and glucan biosynthesis. In the present study, we identified and functionally reannotated another glucan synthase gene, GFGLS2, based on our previous results.
View Article and Find Full Text PDFIn the present study, effects of maturity stage on structural characteristics and biosynthesis/hydrolysis-associated genes expression of glucans from Volvariella volvacea fruit body were well investigated. Elongation and pileus expansion stages decreased total soluble carbohydrate and protein contents to 17.09 mg/g and 8.
View Article and Find Full Text PDFMost of the oleaginous microorganisms cannot assimilate xylose in the presence of glucose, which is the major bottleneck in the bioconversion of lignocellulose to biodiesel. Our present study revealed that overexpression of xylose isomerase (XI) gene xylA or xylulokinase (XK) gene xks1 increased the xylose consumption by 25 to 37% and enhanced the lipid content by 8 to 28% during co-fermentation of glucose and xylose. In xylA overexpressing strain Mc-XI, the activity of XI was 1.
View Article and Find Full Text PDFGrifola frondosa polysaccharides, especially β-glucans, showed the significant antitumor, hypoglycemic, and immune-stimulating activities. In the present study, a predominant regulatory subunit gfRho1p of β-1,3-glucan synthase in G. frondosa was identified with a molecular weight of 20.
View Article and Find Full Text PDFTo elucidate potential roles of UDP-glucose pyrophosphorylase (UGP) in mycelial growth and polysaccharide synthesis of Grifola frondosa, a putative 2036-bp UDP-glucose pyrophosphorylase gene gfugp encoding a 53.17-kDa protein was cloned and re-annotated. Two dual promoter RNA silencing vectors of pAN7-iUGP-P-dual and pAN7-iUGP-C-dual were constructed to down-regulate gfugp expression by targeting its promoter or conserved functional sequences, respectively.
View Article and Find Full Text PDFBacillus coagulans is a thermophilic, facultative anaerobic, spore-forming Gram-positive bacterium, which is used as a probiotic in animal feed and human dietary supplements. In the present study, a bile-resistant thermophilic B. coagulans WT-03 strain was isolated and genetically identified.
View Article and Find Full Text PDFThe aim of this study was to improve the acid tolerance of Lactobacillus acidophilus by combining atmospheric and room temperature plasma (ARTP) mutation with adaptive laboratory evolution (ALE). To achieve a high mutation efficiency, 60 s was determined as the ideal exposure time for ARTP mutation of L. acidophilus with a survival rate of 5.
View Article and Find Full Text PDFA novel macromolecular polysaccharide VGPⅠ-a was purified from Volvariella volvacea fruiting bodies with ultrasound-assisted extraction, ion exchange and gel chromatography. VGPⅠ-a was proved as a α- glucan with Mw of 1435.6 kDa and contained a 1,4-linked d-Glcp backbone with the substitution at C-6 with 1-linked d-Glcp residue.
View Article and Find Full Text PDFLipases or triacylglycerol (TAG) lipases belong to the α/β-hydrolases superfamily, which are enzymes capable of catalyzing the hydrolysis of the ester bond between fatty acids and glycerol. Interestingly, some lipases have been found to not only possess hydrolysis activity but also acyltransferase activity in yeasts and microalgae. Our present study reported a novel dual-functional lipase Lip10 with a slight lipolysis activity but a noteworthy phospholipid/diacylglycerol acyltransferase (PDAT) activity.
View Article and Find Full Text PDFGlucan synthase (GLS) gene is known to be involved in the fungal biosynthesis of cell wall, differentiation, and growth. In the present study, a glucan synthase gene () in the edible mushroom with a full sequence of 5927 bp encoding a total of 1781 amino acids was cloned and characterized for the first time. GFGLSp is a membrane protein containing two large transmembrane domains connected with a hydrophilic cytoplasmic domain.
View Article and Find Full Text PDFAlthough multiple roles of lipases have been reported in yeasts and microalgae, the functions of lipases have not been studied in oleaginous filamentous fungi. Lipase Lip6 has been reported in the oleaginous filamentous fungus Mucor circinelloides with the consensus lipase motif GXSXG and the typical acyltransferase motif of H-(X)-D. To demonstrate that Lip6 might play dual roles as a lipase and an acyltransferase, we performed site-directed mutagenesis in the lipase motif and the acyltransferase motif of Lip6.
View Article and Find Full Text PDFThe influence of 20 standard amino acids was investigated on growth, lipid accumulation, docosahexaenoic acid (DHA) production and cell biochemical composition of Crypthecodinium cohnii. C. cohnii efficiently utilize organic nitrogen (predominantly threonine and to a lesser extent tyrosine and serine) as compared to inorganic nitrogen (NH)SO.
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