D-Allose, a rare sugar, has gained significant attention not only as a low-calorie sweetener but also for its anticancer, antitumor, anti-inflammatory, antioxidant, and other pharmaceutical properties. Despite its potential, achieving high-level biosynthesis of D-allose remains challenging due to inefficient biocatalysts, low conversion rates, and the high cost of substrates. Here, we explored the food-grade coexpression of D-allulose 3-epimerase (Bp-DAE) and L-rhamnose isomerase (BsL-RI) within a single cell using WB800N as the host.
View Article and Find Full Text PDFJUIM01 is an industrial 2-keto-d-gluconate (2KGA)-producing strain. However, its regulation mechanism of 2KGA metabolism remains to be clarified. Among other reported species, the 2-ketogluconate utilization operon ( operon) plays key roles in 2KGA catabolism.
View Article and Find Full Text PDFPrecise regulation of cell division is essential for proper tissue patterning in multicellular organisms. In Arabidopsis, the ground tissue (GT) comprises cortex and endodermis in the early stages of root development. During GT maturation, additional periclinal cell divisions (PCDs) occasionally occur of the endodermis, generating a middle cortex (MC) layer between the cortex and endodermis.
View Article and Find Full Text PDFL-Arabinose isomerase (L-AI) has been commonly used as an efficient biocatalyst to produce D-tagatose via the isomerization of D-galactose. However, it remains a significant challenge to efficiently synthesize D-tagatose using the native (wild type) L-AI at an industrial scale. Hence, it is extremely urgent to redesign L-AI to improve its catalytic efficiency towards D-galactose, and herein a structure-based molecular modification of CY6 L-AI (LpAI) was performed.
View Article and Find Full Text PDFβ-Alanine, a valuable β-type amino acid, is experiencing increased demand due to its multifaceted applications in food flavoring, nutritional supplements, pharmaceuticals, and the chemical industry. Nevertheless, the sustainable biosynthesis of β-alanine currently faces challenges due to the scarcity of robust strains, attributed to the complexities of modulating multiple genes and the inherent physiological constraints. Here, systems metabolic engineering was implemented in to overcome these limitations.
View Article and Find Full Text PDFHerein, a novel multifunctional enzyme β-glucosidase/xylanase/feruloyl esterase (GXF) was constructed by fusion of β-glucosidase and bifunctional xylanase/feruloyl esterase. The activities of β-glucosidase, xylanase, feruloyl esterase and acetyl xylan esterase displayed by GXF were 67.18 %, 49.
View Article and Find Full Text PDFD-allose, a C-3 epimer of D-glucose and an aldose-ketose isomer of D-allulose, exhibits 80% of sucrose's sweetness while being remarkably low in calories and nontoxic, making it an appealing sucrose substitute. Its diverse physiological functions, particularly potent anticancer and antitumor effects, render it a promising candidate for clinical treatment, garnering sustained attention. However, its limited availability in natural sources and the challenges associated with chemical synthesis necessitate exploring biosynthetic strategies to enhance production.
View Article and Find Full Text PDFD-arabitol, a versatile compound with applications in food, pharmaceutical, and biochemical industries, faces challenges in biomanufacturing due to poor chassis performance and unclear synthesis mechanisms. This study aimed to enhance the performance of Zygosaccharomyces rouxii to improve D-arabitol production. Firstly, a mutant strain Z.
View Article and Find Full Text PDF6-Deoxy-l-sorbose (6-DLS) is an imperative rare sugar employed in food, agriculture, pharmaceutical and cosmetic industeries. However, it is a synthetic and very expensive rare sugars, previously synthesized by chemo-enzymatic methods through a long chain of chemical processes. Recently, enzymatic synthesis of rare sugars has attracted a lot of attention due to its advantages over synthetic methods.
View Article and Find Full Text PDFThe CRISPR/Cas9 systems have been developed as tools for genetic engineering and metabolic engineering in various organisms. In this review, various aspects of CRISPR/Cas9 in , from basic principles to practical applications, have been summarized. First, a comprehensive review has been conducted on the history of CRISPR/Cas9, successful cases of gene disruptions, and efficiencies of multiple DNA fragment insertions.
View Article and Find Full Text PDFEmbracing the principles of sustainable development, the valorization of agrowastes into value-added chemicals has nowadays received significant attention worldwide. Herein, was metabolically rewired to convert cellulosic hydrolysate of corn stover into a key platform chemical, namely, 3-hydroxypropionic acid (3-HP). First, the heterologous pathways were introduced into by coexpressing glycerol-3-P dehydrogenase and glycerol-3-P phosphatase in both single and fusion (12) forms, making the strain capable of synthesizing glycerol from glucose.
View Article and Find Full Text PDFD-Allose and D-allulose are two important rare natural monosaccharides found in meager amounts. They are considered to be the ideal substitutes for table sugar (sucrose) for, their significantly lower calorie content with around 80 % and 70 % of the sweetness of sucrose, respectively. Additionally, both monosaccharides have gained much attention due to their remarkable physiological properties and excellent health benefits.
View Article and Find Full Text PDFD-tagatose holds significant importance as a functional monosaccharide with diverse applications in food, medicine, and other fields. This study aimed to explore the oxidoreductive pathway for D-tagatose production, surpassing the contemporary isomerization-mediated biosynthesis approach in order to enhance the thermodynamic equilibrium of the reactions. Initially, a novel galactitol dehydrogenase was discovered through biochemical and bioinformatics analyses.
View Article and Find Full Text PDF3-Hydroxypropionic acid (3-HP) is a top value-added chemical with multifaceted application in chemical, material, and food field. However, limited availability of robust strains and elevated fermentation costs currently impose constraints on sustainable biosynthesis of 3-HP. Herein, transporter engineering, metabolic dynamic modulation, and enzyme engineering were combined to address above limitations.
View Article and Find Full Text PDFFront Bioeng Biotechnol
July 2023
This study aimed to produce enhanced fermentable sugars from a novel stover system through the bioprocessing of its soluble sugars and insoluble carbohydrates. The pretreatment conditions were optimized for this high sugar-containing stover (HSS) to control inhibitor formation and obtain enhanced fermentable sugar concentrations. The optimum temperature, acid loading, and reaction time for the pretreatment were 155 °C, 0.
View Article and Find Full Text PDFD-allulose is a natural rare sugar with important physiological properties that is used in food, health care items, and even the pharmaceutical industry. In the current study, a novel D-allulose 3-epimerase gene (Bp-DAE) from the probiotic strain was discovered for the production and characterization of an enzyme known as Bp-DAE that can epimerize D-fructose into D-allulose. Bp-DAE was strictly dependent on metals (Mn and Co), and the addition of 1 mM of Mn could enhance the half-life of Bp-DAE at 55 °C from 60 to 180 min.
View Article and Find Full Text PDFAims: l-Fuculose is a valuable rare sugar that is used to treat a variety of ailments, including HIV, cancer, Hepatitis B, human lysosomal disease (fucosidosis), and cardio-protective medications. The enzymatic approach for the production of l-fuculose using l-fucose as a substrate would be an advantageous method with a wide range of industrial applications. The objective of this study is the characterization of recombinant l-fucose isomerase from Paenibacillus rhizosphaerae (Pa-LFI) for the production of l-fuculose from an inexpensive and natural source (fucoidan) as well as its comparison with commercial l-fucose (Sigma-Aldrich).
View Article and Find Full Text PDFd-Arabitol, which is typically found in mushrooms, lichens, and higher fungi, might play an effective role in alleviating visceral fat accumulation and insulin resistance particularly for its low calorie and glycemic index. However, the regulatory mechanisms of d-arabitol for alleviating obesity and associated metabolic disorders remain poorly understood. This study aimed to investigate and analyze the underlying relationship between d-arabitol-mediated gut microbiota and obesity.
View Article and Find Full Text PDFMicrobial conversion of bioenergy-derived waste glycerol into value-added chemicals has emerged as an important bioprocessing technology due to its eco-friendliness, feasible technoeconomics, and potential to provide sustainability in biodiesel and bioethanol production. Glycerol is an abundant liquid waste from bioenergy plants with a projected volume of 6 million tons by 2025, accounting for about 10% of biodiesel and 2.5% of bioethanol yields.
View Article and Find Full Text PDF3-Hydroxypropionic acid (3-HP) and 1,3-propanediol (1,3-PDO) are value-added chemicals with versatile applications in the chemical, pharmaceutical, and food industries. Nevertheless, sustainable production of 3-HP and 1,3-PDO is often limited by the lack of efficient strains and suitable fermentation configurations. Herein, attempts have been made to improve the co-production of both metabolites through metabolic engineering of Escherichia coli and process optimization.
View Article and Find Full Text PDFBackground: Microalgae, with their high adaptability to various stress conditions and rapid growth, are considered excellent biomass resources for lipid production and biodiesel feedstocks. However, lipid yield and productivity of the natural strains are common bottlenecks in their large-scale use for lipid production, which can be overcome by evolving new strains using conventional and advanced mutagenic techniques. It is challenging to generate microalgae strains capable of high lipid synthesis through natural selection.
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