Biofuels Bioproducts & Biorefining-Biofpr
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2023
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IF 3.9
Yanping Xie,Xuekun Ma,Abdul Waheed,Muhammad Adnan,Ning Xie,Gang Liu
Cellobiose dehydrogenase (CDH) catalyzes the oxidation of cello-oligosaccharides and transfers electrons to oxygen or other electron receptors, such as lytic polysaccharide oxygenases (LPMOs). Cellobiose dehydrogenase has the potential to be used as an electron donor for LPMOs. Therefore, it is important to obtain CDHs under reaction conditions that are compatible with those of cellulases and LPMOs. Here, a CDH gene from Myceliophthora thermophila ( Mt CDH-A) was constitutively expressed in Trichoderma reesei , and its ability to donate electrons to the LPMO was validated. Mt CDH-A has an optimal pH of 6.0 and maintains relatively high activity over a wide pH range. The optimal temperature was 60°C, and it remained stable at 50°C for a long time. These enzymatic properties were compatible with the catalytic conditions of fungal LPMOs and cellulases. When Mt CDH-A was used as an electron donor, the synergistic effect of LPMO and cellulase improved the degradation efficiency of phosphoric acid-swollen cellulose by 141%. This work provides a novel insight into finding a stable electron donor for LPMOs and a new direction for finding more efficient thermostable CDHs in newly identified fungal species. © 2023 Society of Industrial Chemistry and John Wiley & Sons Ltd.
研究领域:
生物化学
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酶学
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微生物学
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DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
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2026
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IF 3.9
Hu Xu,Niannian Lv,Xiangyu Ren,Yongqin Liu
Cellobiose 2-epimerase (CE) has garnered significant attention for its capability to catalyze the biotransformation of lactose into epilactose, a prebiotic derivative. To date, about 30 distinct species sources of CE have been identified. In this study, a novel CE (Areu-CE) was identified from the psychrotolerant bacterium Arcticibacter eurypsychrophilus , isolated from glaciers on the Tibetan Plateau. This represents the first CE identified from a psychrotolerant species. Areu‑CE exhibits optimal activity at 50 °C toward lactose, achieving a specific activity of 139.7 U mg −1 and a catalytic constant (k cat ) of 169.8 s −1 , reflecting its robust epimerization capability. It also possesses notable substrate affinity, with a K m of 97.8 mM. Importantly, Areu-CE retains substantial activity at 8 °C, yielding 27% epilactose production at a protein concentration of 0.02 mg/mL when utilizing various concentrations of lactose and milk as substrates. These results highlight the potential of Areu-CE for cold-temperature epilactose production and support the value of glacier-derived microorganisms as a resource for cold-active enzyme discovery.
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高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2023
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IF 6.1
Simin Liu,Jiamei Liu,Linguo Zhao,Jianjun Pei
Glycosylation, one of the most common and significant modifications in nature, has prompted the development of a cellobiose phosphorolysis route for glycosylation in vivo. However, the process of glycosylation is hampered by the notably low conversion rate of cellobiose. In this work, regulation of the carbon source supply by changing the ratio of glucose to cellobiose improved the conversion rate of cellobiose, resulting in enhancing the efficiency of glycosylation and the production of vitexin. Moreover, three genes (pgm, agp, and ushA) involved in the degradation of UDP-glucose were knocked out to relieve the degradation and diversion of the cellobiose phosphorolysis route. Finally, through the optimization of conversion conditions, we observed a continuous enhancement in cellobiose conversion rate and vitexin production in BL21ΔushAΔagp-TcCGT-CepA, corresponding to an increased concentration of added glucose. The maximum production of vitexin reached 2228 mg/L with the addition of 2 g/L cellobiose and 6 g/L glucose, which was 312% of that in BL21-TcCGT-CepA with the addition of 2 g/L cellobiose. The conversion rate of cellobiose in BL21ΔushAΔagp-TcCGT-CepA reached 88%, which was the highest conversion rate of cellobiose to date. Therefore, this study presents a cost-effective and efficient method to enhance the conversion rate of cellobiose during the glycosylation process.
研究领域:
生物化学
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代谢工程
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产品关联
DOI
PubMed
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Food Bioscience
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2025
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IF 5.9
Wei Gao,Ru Yang,Mengli Li,Ming Miao,Tao Zhang
Non-food cellulose bioconversion to amylose offers a promising avenue for sustainable biomanufacturing while maximizing non-food biomass utilization. Nevertheless, current α -glucan phosphorylases ( α GPs) exhibit insufficient thermostability and suboptimal catalytic performance, thereby limiting their feasibility for industrial implementation. In this study, a novel thermostable α GP from Dictyoglomus sp. NZ13-RE01 ( Dspα GP) was identified and characterized through computational genome mining. The specific enzyme activity of Dspα GP was 36.3 ± 2.1 U/mg under the optimal conditions of temperature 70 °C and pH 5.0. The enzyme thermal melting temperature ( T m ) was 82.26 °C, and the residual activity retained 55.5 % after stored at 70 °C for 12 h. These results demonstrated the enzyme an exceptional catalytic efficiency and remarkable thermal stability. Kinetic analysis revealed superior substrate specificity toward maltotriose and maltotetraose with k ca t / K m values of 1.96 and 1.83 mM −1 s −1 , respectively. Integration of Dspα GP with Clostridium thermocellum cellobiose phosphorylase established a dual-enzyme cascade system capable of synthesizing amylose with tunable molecular weight (7392–16,632 g/mol) by adjusting the cellobiose/G4 ratio, a conversion efficiency of 35.67 % was achieved, significantly surpassing existing systems. Site-directed mutagenesis combined with molecular docking revealed that conserved residues Gly32, Arg364, Lys370, Tyr432, and Lys464 play critical roles in substrate binding and catalytic processes. This study provides enhanced process efficiency and operational stability for sustainable carbohydrate bioconversion applications and promoting valorization of non-edible cellulose resources.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
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IF 7.7
Jingjie Gao,Shaowei Bai,Fan Wang,Liangzhen Yang,Yufeng Hu,Yuhuan Yang,Bing Bai,Zuoming Zhang
Enzymatic glycosylation is an efficient and biocompatible approach to enhance natural product bioavailability. Cellobiose phosphorylase, a novel glycosyltransferase, utilizes 1-phospho-glucose (1-p-Glc) as a glycosyl donor for regioselective glycosylation of various natural substrates. However, the high cost of 1-p-Glc limits the economic feasibility of the process. Thus, a dual-enzyme cascade system involving cellulase Ac Cel9A and cellobiose phosphorylase Cb CBP using a co-immobilization strategy was developed to overcome this challenge. The system utilizes low-cost carboxymethyl cellulose (CMC) for continuous 1-p-Glc production, which was then used in the fluorodeoxy glucose (FDG) glycosylation to generate fluorodeoxy cellobiose (FDC), which potentially traces fungal infections. The compartmentalized co-immobilization of the two enzymes within the internal and external regions of a porous zeolitic imidazolate framework-8 (ZIF-8) carrier enhanced the overall stability of the dual-enzyme system. The immobilized enzymes retained approximately 63.3 % activity after seven reuse cycles and 74 % catalytic efficiency after 12 days of storage at room temperature. Therefore, the developed co-immobilized multi-enzyme system holds significant potential for industrial biocatalysis applications.
研究领域:
生物化学
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工业酶学
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合成生物学
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CHEMOSPHERE
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2021
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IF 7.086
Xin-Yu Wang,Yang Hao,Hong-Bo Zhao,Yuan-Ru Guo,Qing-Jiang Pan
The interfacial chemistry of nanocomposite materials is of overarching importance in the separation and purification science; moreover, its understanding helps to guide synthesis, clarify structure-property relationship and unearth novel applications. However, the composites feature rather complicated local structures and hydrogen bonds are often involved in the interface and the vicinity of active sites. In this regard, density functional theory first-principle calculations associated with experimental study have synergistically examined two-dimensional (2D) magnesium hydroxide material with different layers and their adsorption toward cellobiose. Hydrogen bonds are found responsible for the interfacial coupling, which make it vital to cover the dispersion correction in the calculation. The average adsorption energy ranges from −0.29 to −0.35 eV, falling well within the range of reported hydrogen-bonding strength. On the basis of calculated structural/interfacial properties and experimental findings, the 2D Mg(OH) 2 in terms of three-layer model was unraveled to substitute toxic Cd 2+ ion and sorb radioactive UO 2 2+ that is coordinated by water and hydroxyl groups. These reactions are thermodynamically feasible. The ion-exchanging mechanism was proposed for cadmium removal and the outer-sphere adsorption one for uranium extraction.
研究领域:
材料科学
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环境科学
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产品关联
DOI
PubMed
高影响因子
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