Molecular Catalysis
·
2022
·
IF 5.089
Hengtao Tang,Zheng Zhou,Zhi Chen,Xin Ju,Liangzhi Li
Monosaccharides from biomass can be used as cost-effective raw materials to produce rare sugars which are valuable sweeteners. Enzymes play a pivotal role in such biomass biorefinery processes to develop novel synthetic routes, and improve the environmental friendliness of current routes. Here we propose a proof of concept biorefinery process to prepare useful rare sugars of D-xylulose and D-ribulose from D-xylose which was abundant in biomass. Ribose-5-phosphate isomerase B from Ochrobactrum sp. (OsRpiB) with a unique substrate scope was engineered to intensify the activity of transforming D-xylose to D-xylulose. A double mutant R94N/N137Q with 80% higher catalytic efficiency was identified, and kinetic and molecular dynamic studies were conducted to explore the mechanism underneath. The results revealed a correlation between enhancing stability and activity simultaneously. Then a one-pot enzyme cascade was constructed with OsRpiB and D-tagatose-3-epimerase from Pseudomonas cichorii and transformed D-xylulose further to D-ribulose. The conversions of D-xylose and D-xylulose in cascade reaction were 1.80-fold and 1.83-fold of that in separate reactions with the aid of process parameter adjustment. The presented work is the first reported enzyme cascade converting D-xylose to D-ribulose, and proves the promising role of monosaccharide isomerase platforms in the refinery of biomass.
研究领域:
生物化学
·
酶工程
·
生物质精炼
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Xinyu Wang,Sichen Huo,Yanjie Chen,Mingyi Wang,Ying Dai,Jinlong Zou
Cobalt atom cluster (Co AC )-based electrocatalysts usually exhibit high activity for oxygen reduction reaction (ORR), but display limited performance in oxygen evolution reaction (OER). To enhance their bifunctional catalytic efficiency, it is crucial to tailor the d -orbital electronic structure of Co AC through orbital coupling effect, optimizing the chemisorption of O-intermediates. Herein, a 3 d -4 d orbital coupling strategy is used to construct a Co AC -molybdenum carbide/nanocarbon cake (Co AC -Mo x C/CC) catalyst with a hollow structure for ORR/OER in zinc-air batteries (ZABs). Experimental and theoretical results confirm that the 4 d transition metal Mo, with fewer d electrons and more unfilled orbitals, interacts strongly with Co sites through d - d coupling, promoting electron enrichment and triggering 3 d -orbital electron delocalization. This process accelerates the rate-limiting steps of *OH desorption for ORR and *OOH formation for OER, leading to an ultra-low potential gap of 0.604 V and improved stability. Notably, the Co AC -Mo x C/CC-based liquid and flexible all-solid-state ZABs exhibit excellent performance with high open-circuit voltages of 1.49 and 1.47 V, and power densities of 146.4 and 103.4 mW cm −2 , respectively, highlighting their potential to replace precious metal catalysts. This study may open new avenues for manipulating the electronic properties of Co AC -based electrocatalysts and boosting activity through the d - d orbital coupling strategy.
研究领域:
材料科学
·
电化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Foods
·
2022
·Vol. 11
·期 20
·3225
·
IF 5.561
Xinrui Tang,Yingfeng An,Muhammad Waheed Iqbal,Hongri Cong,Guoyan Zhang,Yufei Zhang,Yuvaraj Ravikumar,Hossain M. Zabed,Mei Zhao,Haixing Zhou,Xianghui Qi
D-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 strainBlautia producawas 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 (Mn2+and Co2+), and the addition of 1 mM of Mn2+could enhance the half-life of Bp-DAE at 55 °C from 60 to 180 min. It exhibited optimal activity in a pH of 8 and 55 °C, and theKmvalues of Bp-DAE for the different substrates D-fructose and D-allulose were 235.7 and 150.7 mM, respectively. Bp-DAE was used for the transformation from 500 g/L D-fructose to 150 g/L D-allulose and exhibited a 30% of conversion yield during biotransformation. Furthermore, it was possible to employ the food-grade microbial speciesBacillus subtilisfor the production of D-allulose using a technique of whole-cell catalysis to circumvent the laborious process of enzyme purification and to obtain a more stable biocatalyst. This method also yields a 30% conversion yield.Keywords:D-allulose 3-epimerase;D-allulose;Blautia produca;probiotics;biochemical characterization;biotransformation
研究领域:
生物化学
·
生物技术
·
食品科学
·
药学
✓ 已验证
DOI
PubMed
高影响因子
ENGINEERING IN LIFE SCIENCES
·
2019
·Vol. 19
·期 4
·270-278
·
IF 1.936
Jinyuan Hu,Xiao Lu,Haokun Wang,Fuxiang Wang,Yuan Zhao,Wei Shen,Haiquan Yang,Xianzhong Chen
d -Alanyl- d -alanine carboxypeptidase DacC is important for synthesis and stabilization of the peptidoglycan layer of Escherichia coli . In this work, dacC of E . coli BL21 (DE3) was successfully deleted, and the effects of this deletion on extracellular protein production in E . coli were investigated. The extracellular activities and fluorescence value of recombinant amylase, green fluorescent protein, and α-galactosidase of the deletion mutants were increased by 82.3, 29.1, and 37.7%, respectively, compared with that of control cells. The outer membrane permeability and intracellular soluble peptidoglycan accumulation of deletion mutant were also enhanced compared with those of control cells, respectively. Based on fluorescence-assisted cell sorting analyses, we found that the morphology of the E. coli deletion mutant cells was altered compared with that of control cells. Local transparent bulges in the poles of the E . coli mutant with deletion of the dacC gene were found by transmission electron microscopy analysis. These bulges in the poles could explain the improvement in the production of extracellular protein by the E. coli mutant with deletion of the dacC gene. These findings provide important insights into the extracellular production of proteins using E . coli as microbial cell factories.
研究领域:
微生物学
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生物技术
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
CATALYSIS TODAY
·
2014
·
IF 3.309
Senlin Wang,Wei Wei,Yu Zhao,Hexing Li,Hui Li
In this paper, highly ordered mesoporous silica nanospheres externally covered by methyl groups ( CH 3 ) but internally grafted by aminopropyl groups ( NH 2 ) were used as host matrix for loading Ru–B amorphous alloy nanoparticles (NPs). The NH 2 and the CH 3 groups served synergistically as effective functionalities for highly dispersing Ru–B NPs within the pore channels of the mesoporous host. Such catalyst was used in the liquid-phase d -glucose hydrogenation and delivered much higher activity than industrial Raney Ni and the commercial Ru/C catalysts. Meanwhile, it could be used repetitively for more than 9 times, showing a good potential in practical applications. This work demonstrated that the surface properties of mesoporous materials can be modified through region-selective immobilization of diverse organic groups, which is essential to optimize the catalysis for some reactions.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2022
·
IF 3.705
Lei Wang,Kecai Chen,Peng Zheng,Xiang Huo,Fei Liao,Liping Zhu,Meirong Hu,Yong Tao
D -Psicose, a new-generation sugar substitute, has been enzymatically synthesized through D -fructose isomerization. However, isomerization often causes low yields due to unfavorable thermodynamic equilibria, which limited its further industrial application. In this study, we present a redox-driven multi-enzyme cascade, two-step biotransformation system to produce D -psicose from D -fructose. Compared to D -fructose isomerization, this method has a maximized theoretical conversion rate of 100%. D -Psicose-3-epimerase from Clostridiales (CBDPE), ribitol 2-dehydrogenase from Providencia alcalifaciens (PRDH), and formate dehydrogenase from Starkeya (SFDH) were co-expressed in Escherichia coli in the first step to produce D -allitol from D -fructose. Afterward, NADH oxidase from Streptococcus pyogenes (SPNOX), and ribitol 2-dehydrogenase from Rubrivivax sp. (RSRDH) were co-expressed in E. coli to oxidize D -allitol into D -psicose in the second step. The two-step biotransformation system was optimized to maximize the D -fructose-to- D -psicose conversion rate (up to 90%), corresponding to a concentration of 450 mM. This study suggests that this redox-driven multi-enzyme cascade strategy through a sugar-to-alcohol-to-sugar pathway has the advantage of great application for enhanced production of D -psicose and other rare sugars.
研究领域:
生物化学
·
生物技术
·
酶学
·
代谢工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TOXICOLOGY AND APPLIED PHARMACOLOGY
·
2018
·
IF 3.616
Guolin Zhao,Muhanad Elhafiz,Jingwei Jiang,Debanjan Das,Zhijian Li,Wang Zhou,Sisi Fan,Changling Wang,Ziqiao Yuan,Dengqiu Xu,Zhenzhou Jiang,Luyong Zhang,Tao Wang
8-methoxypsoralen (8-MOP) with ultraviolet A radiation therapy (PUVA) is the standard therapy for patients with psoriasis , despite the reported potential risks of 8-MOP-induced cholestatic liver injury in both humans and animals. Usually, patients with chronic cholestasis exhibit lower serum 25-hydroxy vitamin D (25(OH)D) levels. But those patients receiving PUVA for psoriasis showed an increase in serum 25(OH)D levels, probably highlighting that the vitamin D–vitamin D nuclear receptor (VD-VDR) axis play a protective role in 8-MOP-induced hepatotoxicity. The present study confirmed 8-MOP could increase serum 25(OH)D levels in conventional lighting and diet (CLD) and vitamin D deficient (VDD) Sprague-Dawley rats. Potential liver risks were also found in CLD and VDD rats after 8-MOP treatment. We proved that 8-MOP could be a potent ligand for VDR using molecular docking and luciferase report assay. Effect of 8-MOP on VDR subcellular distribution was determined using human liver cell line L02. We found 8-MOP could increase VDR protein expression in the nuclear and cytosol extracts and also total cell extracts in L02. siRNAs for VDR were used to determine the role of VDR in protecting 8-MOP-induced cholestasis and potential cellular mechanisms. The results showed 8-MOP could affect the CYP7A1 , SHP and MRP3 expression via VDR, and such effects could be reversed by knockdown of VDR expression, suggesting a vital role of VDR involved in 8-MOP-regulated bile acid synthesis and transportation. In conclusion, these results revealed activation of VD–VDR axis may play a beneficial role in 8-MOP-mediated regulation of bile acid synthesis and transportation.
研究领域:
药理学
·
毒理学
·
分子生物学
·
肝病学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2021
·
IF 5.279
Zhaohui Guo,Christian M. Pedersen,Pengfei Wang,Minjun Ma,Yingqing Zhao,Yan Qiao,Yingxiong Wang
The isomerization of d-glucose to d-fructose plays a key role in the biochemical and chemical conversion of biomass, and it is therefore desirable to develop and improve catalysts for this reaction. In this study, the environmentally friendly polymer poly(amidoamine) (PAMAM) dendrimer’s properties as catalysts for this isomerization are investigated. The experimental results showed that the PAMAM dendrimers, which have basic terminal groups, can effectively promote the d-glucose isomerization reaction. Under the optimized reaction conditions, d-fructose was generated with a 20% maximum yield and above 90% selectivity. 13C and 2H isotope experiments by NMR were carried out to explore the reaction mechanism. When the reaction was performed in D2O, the C1 signal of d-fructose changed to a triplet, which confirmed that the C1 carbon binds to a deuterium atom, i.e., isotopic exchange. It was also found that the deuterium atom at the C2 position of d-glucose-2-d1 cannot transfer to d-fructose. These data indicate that PAMAM dendrimers catalyze d-glucose isomerization through a mechanism, which includes deprotonation, formation of ene-diol intermediate, and proton exchange with the solvent.
研究领域:
生物化学
·
绿色化学
✓ 已验证
DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2024
·
IF 3.4
Dingyu Guo,Zhengchao Wang,Wanqing Wei,Wei Song,Jing Wu,Jian Wen,Guipeng Hu,Xiaomin Li,Cong Gao,Xiulai Chen,Liming Liu
D-allulose is a naturally occurring rare sugar and beneficial to human health. However, the efficient biosynthesis of D-allulose remains a challenge. Here, we mined a new D-tagatose 3-epimerase from Kroppenstedtia eburnean (KeDt3e) with high catalytic efficiency . Initially, crucial factors contributing to the low conversion of KeDt3e were identified through crystal structure analysis, density functional theory calculations (DFT), and molecular dynamics (MD) simulations. Subsequently, based on the mechanism, combining restructuring the flexible region, proline substitution based onconsensus sequence analysis, introducing disulfide bonds , and grafting properties, and reshaping the active center, the optimal mutant M5 of KeDt3e was obtained with enhanced thermostability and activity. The optimal mutant M5 exhibited an enzyme activity of 130.8 U/mg, representing a 1.2-fold increase; T m value increased from 52.7 °C to 71.2 °C; and half-life at 55 °C extended to 273.7 min, representing a 58.2-fold improvement, and the detailed mechanism of performance improvement was analyzed. Finally, by screening the ribosome-binding site (RBS) of the optimal mutant M5 recombinant bacterium (G01), the engineered strain G08 with higher expression levels was obtained. The engineered strain G08 catalyzed 500 g/L D-fructose to produce 172.4 g/L D-allulose, with a conversion of 34.4% in 0.5 h and productivity of 344.8 g/L/h on a 1 L scale. This study presents a promising approach for industrial-scale production of D-allulose.
研究领域:
生物化学
·
食品科学
·
酶工程
✓ 已验证
DOI
PubMed
高影响因子
ACS Food Science & Technology
·
2021
·
IF 0
Xiaoyan Chen,Fan Wang,Shijie Liu,Qiang Yu,Wen Wang,Yu Zhang,Zhongming Wang,Zhenhong Yuan
The synthesis efficiency of d-allulose, an ideal sugar substitute and dietary supplement, from d-glucose with whole-cell catalysts was improved by three out of the four tested deep eutectic solvents (DESs) based on choline chloride (ChCl). The promotion effects on the product yields with increments of up to 2.6-fold were observed in reactions with the presence of DESs in the order ChCl/glycerol < ChCl/urea < ChCl/ethylene glycol. DES compositions displayed distinct influences, but all positive effects appeared in the reactions with low DES contents (1–10%). Higher DES contents produced negative effects, and 40% even totally suppressed the reaction. The enhancement of efflux of intracellular molecules was proved by an analysis of the nucleic acid and protein contents in the medium. DES assisted in the increase in cell membrane permeability rather than in the damage of cell wall integrity, accelerating quick contacts between the enzyme and substrate and improving the conversion rate.
研究领域:
化学工程
·
生物化学
·
食品科学
✓ 已验证
DOI
Frontiers in Chemistry
·
2020
·
IF 3.693
Wang Yang,Ravikumar Yuvaraj,Zhang Guoyan,Yun Junhua,Zhang Yufei,Parvez Amreesh,Qi Xianghui,Sun Wenjing
D-allulose, which is one of the important rare sugars, has gained significant attention in the food and pharmaceutical industries as a potential alternative to sucrose and fructose. Enzymes belonging to the D-tagatose 3-epimerase (DTEase) family can reversibly catalyze the epimerization of D-fructose at the C3 position and convert it into D-allulose by a good number of naturally occurring microorganisms. However, microbial synthesis of D-allulose is still at its immature stage in the industrial arena, mostly due to the preference of slightly acidic conditions for Izumoring reactions. Discovery of novel DTEase that works at acidic conditions is highly preferred for industrial applications. In this study, a novel DTEase, DTE-CM, capable of catalyzing D-fructose into D-allulose was applications. In this study, a novel DTEase, DTE-CM, capable of catalyzing D-fructose into D-allulose was DTE-CM on D-fructose was found to be remarkably influenced and modulated by the type of metal ions (co-factors). The DTE-CM on D-fructose was found to be remarkably influenced and modulated by the type of metal ions (co-factors). The 50°C from 0.5 to 3.5 h at a concentration of 0.1 mM. The enzyme exhibited its maximum catalytic activity on D-fructose at pH 6.0 and 50°C from 0.5 to 3.5 h at a concentration of 0.1 mM. The enzyme exhibited its maximum catalytic activity on -fructose at pH 6.0 and 50°C with a Kcat/Km value of 45 mM−1min−1. The 500 g/L D-fructose, which corresponded to 30% conversion rate. With these interesting catalytic properties, this enzyme could be a promising candidate for industrial biocatalytic applications.
研究领域:
食品科学
·
生物化学
·
酶学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Energy Storage
·
2025
·
IF 9.8
Xuhui Li,Menghan Zhang,Mengyang Yin,Xingming Ning,Zhongwei An,Xinbing Chen,Pei Chen
Advancing flexible zinc-air batteries (ZABs) hinges on efficient bifunctional oxygen electrocatalysts, yet resolving the intrinsic activity trade-off between oxygen reduction (ORR) and evolution reactions (OER) remains a long-standing scientific challenge. Herein, we propose a molecular engineering strategy to optimize the electronic configuration of Fe centers in an iron‑cobalt tetranitro-phthalocyanine complex (FeCoPc-NO 2 ), by Co atoms and electron-withdrawing nitro groups. Density functional theory and electrochemical characterizations unveil that a weak d-d coupling between adjacent Fe/Co atoms tailors the Fe 3d-orbital electron density and the adsorption energies of oxygen-containing intermediates, boosting OER activity (η 10 = 320 mV) and concurrently retaining high ORR performance (E 1/2 = 0.81 V vs. RHE). Moreover, the assembled flexible ZABs achieve a peak power density of 74.9 mW·cm −2 , high round-trip efficiency (65.8 %), prolonged cycling stability (48 h), and mechanical robustness (>90° bending). This study validates the feasibility of atomically precise molecular design in creating bifunctional electrocatalysts with exceptional performance and cost efficiency.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源存储与转换
·
分子工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）