APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
·
IF 14.229
Yu-Xuan Xiao,Jie Ying,Ge Tian,Yong Tao,Hao Wei,Si-Yu Fan,Ze-Hao Sun,Wan-Juan Zou,Jie Hu,Gang-Gang Chang,Weihua Li,Xiao-Yu Yang,Christoph Janiak
The strong Pt-carbon interaction is a very promising way to high-performance design of electrocatalysts. However, the heavy d-π overlap, a high strength of Pt-C bonding, in sp 2 bonded graphitic carbons with low level of defects is rarely reported. Herein, PtPd nanoparticles and graphitic carbon nanofibers (PtPd/CNF) have been integrated via heavy d-π overlap by an interfacial wettability approach and their formation mechanism has also been fully elucidated. The features of strong d-π overlap and high dispersion of metals offer PtPd/CNF with enhanced ORR activity (5.8 folds of specific activity than commercial Pt/C), and excellent structural stability and electrocatalytic durability. A new “heavy d-π overlap” concept, characteristics, and mechanism are proposed at an atomic-/nanoscale to clarify the generation of the predictive interaction as well as the interface charge transfer. It is believed that the study on heavy d-π overlap sheds new light on the fundamental aspects of the nature of Pt-C interaction.
研究领域:
材料科学
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电化学
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纳米技术
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产品关联
DOI
高影响因子
Food Bioscience
·
2024
·
IF 4.8
Han Zhang,Zhen Sun,Xinling Du,Qianqian Cheng,Fuchun Ji,Zishen Nie,Julei Zhan,Zhouping Wang,Aitao Li,Irina Delidovich,Yu Xia
d- Allulose is a rare sugar with multiple physiological functions whose application has been restricted by low conversion rate, weak thermostability of the used enzymes, and complex production. In this study, a simplified multienzyme cascade strategy was designed for biosynthesis of d- allulose from d- glucose, and a detailed investigation of the crucial enzyme allulose 6-phosphate phosphatase was conducted. Under optimized conditions, the yield of d- allulose reached 4.12 ± 0.14 and 80.20 ± 3.20 mmol/L using 10.0 and 200.0 mmol/L d- glucose as substrate, respectively. Furthermore, the influence of various factors on the cooling crystallization of d- allulose was investigated, and the crystallization process was optimized. Consequently, a crystallization recovery rate of 77.43% ± 2.50% and a purity of 98.70% ± 0.05% were achieved. Moreover, the obtained crystals of d -allulose were characterized by XRD, TGA-DSC, and optical microscopy.
研究领域:
生物化学
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食品科学
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产品关联
DOI
高影响因子
BIOORGANIC CHEMISTRY
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2025
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IF 4.7
Ruobin Sun,Qipeng Yan,Wenhao Deng,Pengcheng Chen,Dan Wu,Pu Zheng
Achieving enzyme catalysis at high substrate concentrations is a substantial challenge in industrial biocatalysis, and the role of glycosylation in post-translational modifications that modulate enzyme substrate inhibition remains poorly understood. This study provides insights into the role of N -glycosylation in substrate inhibition by comparing the catalytic properties of d -lactonohydrolase ( d -Lac) derived from Fusarium moniliforme expressed in prokaryotic and eukaryotic hosts. Experimental evidence indicates that recombinant d -Lac expressed in Pichia pastoris ( Pp Lac-WT) exhibits higher hydrolysis rates at a substrate concentration of 400 g/L, with reduced substrate inhibition and enhanced stability compared to the recombinant d -Lac expressed in Escherichia coli ( Ec Lac-WT). Mutant Pp Lac-M1 achieves a conversion rate of 40 % at a substrate concentration of 400 g/L, with a space–time yield of d -pantoic acid reaching 91.1 g/L/h. Proteomics analysis reveals that residues N29 and N278, located approximately 10–20 Å from the active site undergo N -glycosylation in Pp Lac-WT. Using microsecond-scale molecular dynamics simulations and Markov state models, we elucidate the effects of glycosylation on the conformational flexibility of two key loops at the entrance of the binding pocket. Specifically, the loops in Pp Lac-WT can transition between open and closed states, whereas those in Ec Lac-WT tend to remain open. In high substrate concentration conditions, the open state causes congestion, leading to substrate inhibition. Shortest-path map analysis confirms that substrate entry is dynamically controlled by residue N29 on the loops surrounding the active site. Our findings enhance the understanding of the effects of glycosylation on enzyme conformational dynamics and provide insights into mitigating inhibition at high substrate concentrations.
研究领域:
生物化学
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酶工程
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结构生物学
✓ 已验证
DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2024
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IF 8.5
Jing Sun,Zaixu Wang,Yongjin Dai,Moran Zhang,Xinyi Pang,Xiangfei Li,Yingjian Lu
Molds and mycotoxins pose severe threats to health. Bacillomycin D (BD) can effectively inhibit mold growth. Attapulgite (ATP) can provide a good carrier for antimicrobial agents. Natural ATP was acid-modified to obtain H-ATP. It was used to load BD to obtain a novel composite material (H-ATP-BD). The results showed H-ATP had better adsorption performance than ATP. BD was adsorbed up to 93.13 % by adding 30 mg H-ATP and stirring at 40 ℃ for 120 min. Fourier transform infrared spectra (FTIR), size and zeta potential, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) results confirmed successful loading of BD onto H-ATP. The composite showed good inhibition of Aspergillus and adding 0.6 % H-ATP-BD composite was effective in removing 89.06 % of aflatoxin B 1 (AFB 1 ) at 50 °C. Model fitting indicated that AFB 1 removal was a spontaneous exothermic reaction. This research will lay the foundation for the development of efficient and green antimicrobial and toxin-reducing materials.
研究领域:
食品科学
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微生物学
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材料科学
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产品关联
DOI
PubMed
高影响因子
Biology-Basel
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2025
·Vol. 14
·期 3
·226
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IF 3.5
Zonghan Jiang,Leisheng Sun,Yuanyuan Li,Haoyu Li,Yu Fu,Jiyun Li,Zhiliang Sun
Simple SummaryEscherichia coliis a ubiquitous pathogen, with certain strains causing severe diarrhea and intestinal illnesses, which pose significant health risks to both children and animals. As antimicrobial resistance continues to rise, traditional antibiotics are increasingly ineffective, highlighting the urgent need for novel therapeutic strategies. In this study, we investigated the antimicrobial peptide D-CONGA-Q7, aiming to evaluate its efficacy and underlying mechanism against drug-resistantE. colistrains. Our results demonstrate that D-CONGA-Q7 effectively disrupts bacterial cell membranes, leading to bacterial death, and exhibits comparable activity against polymyxin- and meropenem-resistant strains. In vivo experiments revealed that D-CONGA-Q7 significantly alleviated intestinal inflammation, reduced inflammatory cytokine levels, and promoted the repair of damaged intestinal tissues. Furthermore, D-CONGA-Q7 displayed good stability. These findings suggest that D-CONGA-Q7 not only represents a promising new approach to combat drug-resistant bacterial infections but also holds potential for clinical application.Escherichia coli(E. coli) is a zoonotic bacterium widespread in the environment, highly transmissible, and responsible for significant economic losses and millions of cases of illness annually. The rise of multidrug-resistant (MDR) strains has rendered last-line antibiotics such as polymyxin and meropenem ineffective, making the development of new antibiotics urgent. Although D-CONGA-Q7 has broad-spectrum bactericidal activity, its underlying mechanism remains poorly understood. In this study, we used in vitro and in vivo experiments to demonstrate that D-CONGA-Q7 effectively kills both antibiotic-sensitive and multidrug-resistant strains ofE. coli. D-CONGA-Q7 disrupts the cell membranes of Gram-negative bacteria, and the treatment ofE. colistrainLN175with D-CONGA-Q7 resulted in a significant up-regulation of theMlacgene, suggesting that D-CONGA-Q7 may interact with phospholipids in the cell membrane. Furthermore, in treatingK88-induced bacterial enteritis in the small intestine, D-CONGA-Q7 significantly reduced intestinal inflammation. In conclusion, this study provides a novel approach to combat drug-resistantE. coli.
研究领域:
微生物学
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药理学
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传染病学
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产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
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2017
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IF 4.811
Guoguang Wei,Alei Zhang,Kequan Chen,Pingkai Ouyang
This study presents an efficient pretreatment of crayfish shell using high pressure homogenization that enables N -acetyl- d -glucosamine (GlcNAc) production by chitinase. Firstly, the chitinase from Serratia proteamaculans NJ303 was screened for its ability to degrade crayfish shell and produce GlcNAc as the sole product. Secondly, high pressure homogenization, which caused the crayfish shell to adopt a fluffy netted structure that was characterized by Scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD), was evaluated as the best pretreatment method. In addition, the optimal conditions of high pressure homogenization of crayfish shell were determined to be five cycles at a pressure of 400 bar, which achieved a yield of 3.9 g/L of GlcNAc from 25 g/L of crayfish shell in a batch enzymatic reaction over 1.5 h. The results showed high pressure homogenization might be an efficient method for direct utilization of crayfish shell for enzymatic production of GlcNAc.
研究领域:
生物化学
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废弃物利用
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酶工程
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产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2019
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IF 2.931
Qi Wang,Lingfang Li,Tingxuan Wu,Xiangpeng Kong,Qingguo Ma,Chunlei Ma
Taking consideration of metal-induced fluorescence quenching and excellent coordination effect of D-penicillamine (D-PA), a graphene quantum dots (GQDs)-based fluorescent switch for D-PA detection was designed and established firstly with the help of lead ions . GQDs obtained from citric acids made them rich in carboxyl and hydroxyl groups , giving GQDs the ability to combine with lead ions. As anticipated, the fluorescence intensity was quenched by Pb 2+ through electron transfer process. Further, the addition of D-PA effectively recovered the fluorescence due to the departure of Pb 2+ from GQDs aroused by the strong coordination between D-PA and Pb 2+ . Thus, a fluorescent switch was activated for D-PA detection. The fluorescence recovery efficiencies were found to be proportional to the concentration of D-PA in the range of 0.6–50 μmol L − 1 and the detection limit was 0.47 μmol L − 1 . The real sample detection was performed in human urea sample and satisfactory recoveries of 96.84%–102.13% were obtained. The GQDs-Pb 2+ based fluorescent switch sensing method was firstly established with low detection limit and wide linear range, making it a supplement and improvement for D-PA detection.
研究领域:
分析化学
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生物医学
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产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
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2018
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IF 5.123
Yifan Chen,Juan Qiao,Qianrong Liu,Mingming Zhang,Li Qi
Papain-stabilized gold nanoclusters ( [email protected] ) with a red fluorescence emission at 639 nm have been generated successfully in aqueous solution. The fluorescence of [email protected] could be quenched in the addition of Cu 2+ . Subsequently, a unique fluorescent probe based on [email protected] 2+ complex has been constructed for sensitive, selective and “turn-on” detection of D-penicillamine (D-pen). The sensing probe has exhibited a remarkable fluorescence enhancement in the presence of D-pen, which can be measured ranging from 30.0 μM to 2.0 mM (r 2 = 0.991) with the detection limit of 5.0 μM. Furthermore, the developed assay has been utilized to explore the metabolic process of D-pen in rats after intraperitoneal injection. As far as we concerned, the present study has reported the first analytical method for sensing serum D-pen in real time by using the fluorescent [email protected] 2+ complex. Our strategy paves a way for digging up the biological and clinical application of the fluorescent AuNCs.
研究领域:
分析化学
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生物医学
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纳米技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF BIOTECHNOLOGY
·
2024
·
IF 4.1
Yufeng Zhou,Xiaolong Sun,Jiahuan Hu,Yingjie Miao,Xiangyu Zi,Xi Luo,Yongqian Fu
Serving as a vital medical intermediate and an environmentally-friendly preservative, D-PLA exhibits substantial potential across various industries. In this report, the urgent need for efficient production motivated us to achieve the rational design of lactate dehydrogenase and enhance catalytic efficiency . Surprisingly, the enzymatic properties revealed that a mutant enzyme , Lr LDH T247I/D249A/F306W/A214Y ( Lr LDH-M 1 ), had a viable catalytic advantage. It demonstrated a 3.3-fold increase in specific enzyme activity and approximately a 2.08-fold improvement of K cat . Correspondingly, molecular docking analysis provided a supporting explanation for the lower K m and higher K cat /K m of the mutant enzyme. Thermostability analysis exhibited increased half-lives and the deactivation rate constants decreased at different temperatures (1.47–2.26-fold). In addition, the mutant showed excellent resistance abilities in harsh environments, particularly under acidic conditions. Then, a two-bacterium ( E. coli /pET28a- lrldh -M 1 and E. coli /pET28a- ladd ) coupled catalytic system was developed and realized a significant conversion rate (77.7%) of D-phenyllactic acid, using 10 g/L L-phenylalanine as the substrate in a two-step cascade reaction.
研究领域:
生物化学
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酶工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2021
·Vol. 193
·期 7
·2029-2042
·
IF 2.926
Xu Jian-Miao,Cao Hui-Ting,Wang Ming,Ma Bao-Jian,Wang Liu-Yu,Zhang Kai,Cheng Feng,Xue Ya-Ping,Zheng Yu-Guo
d -amino acid oxidase (DAAO) is widely used in the industrial preparation of l -amino acids, and cultivating Escherichia coli ( E. coli ) expressing DAAO for the biosynthesis of l -phosphinothricin ( l -PPT) is very attractive. At present, the biomass production of DAAO by fermentation is still limited in large-scale industrial applications because the expression of DAAO during the fermentation process inhibits the growth of host cells, which limits higher cell density. In this study, the factors that inhibit the growth of bacterial cells during a 5-L fed-batch fermentation process were explored, and the fermentation process was optimized by co-expressing catalase (CAT), by balancing the biomass and the enzyme activity, and by adding exogenous d -alanine ( d -Ala) to relieve the limitation of DAAO on the cells and optimize fermentation. Under optimal conditions, the DO-STAT feeding mode with DO controlled at 30% ± 5% and the addition of 27.5 g/L lactose mixed with 2 g/L d -Ala during induction at 28 °C resulted in the production of 26.03 g dry cell weight (DCW)/L biomass and 390.0 U/g DCW specific activity of DAAO; an increase of 78% and 84%, respectively, compared with the initial fermentation conditions. The fermentation strategy was successfully scale-up to a 5000-L fermenter.
研究领域:
生物技术
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微生物学
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酶学
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工业发酵
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
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IF 8.1
Fang Li,Haili Lin,Huiqin Yu,Xuemei Jia,Shifu Chen,Jing Cao
Replacing the sluggish oxygen evolution reaction with the oxidation of benzyl alcohol to construct the hybrid water electrolysis system has been attractive for its merits of environmentally friendly and economically efficient. However, the activity of the catalyst to oxidize alcohols needs to be further improved. Tailoring the d-band center (E d ) has been proven as an effective method to promote the hydrogen evolution reaction (HER). How feasible is this strategy in the oxidation of benzyl alcohol? Here, using Co 2 C as a research platform, the doping nonmetal heteroatom (P, S, N) engineering is adopted to promote its electrocatalytic BA oxidation and HER performance. The results of electrochemical tests show that the P-doped Co 2 C (P–Co 2 C) only requires a low potential of 1.33 and 1.38 V vs. RHE to achieve current densities of 20 and 100 mA cm −2 for BA oxidation, which is superior to that of S–Co 2 C, N–Co 2 C, and pristine Co 2 C. The conversation and faradaic efficiency for BA is up to 98.1% and 93.8% during ten consecutive cycle tests. The P–Co 2 C also exhibited outstanding activity and stability toward HER. The density functional theory (DFT) calculation revealed that specified P doping could modify the d-band center of Co 2 C approaching the peak of the volcano map (electrochemical overpotentials ∼ E d ). The Gibbs free energy of the BA oxidation was also reduced, thus optimizing the adsorption and desorption process of intermediates. On the other hand, the catalyst surface physical properties of Co 2 C such as hydrophilicity was promoted by the doped heteroatoms which was favorable for the gas-liquid-solid triphase electrocatalytic reaction. This work offers a facial perception of regulating the d-band to design advanced bifunctional electrocatalysts for organic matter oxidation and HER.
研究领域:
电化学
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材料科学
·
催化化学
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
·
2017
·Vol. 50
·期 9
·748-753
·
IF 0.629
Zhaoyu Wang,Rongling Yang,Jizhong Wang,Yanhong Bi,Chun Zhu,Xiangjie Zhao,Linghong Nie,Wenqian Li
Regioselective enzymatic glycosylation of D-glucose and various structural alcohols for synthesizing β-D-glucopyranosides was successfully conducted. Among the β-glycosidases from seven potential plant seeds, the low-cost β-glycosidase from Prunus persica seed displayed excellent activity for salidroside preparation. Several crucial parameters, such as the solvent, buffer pH, buffer content, substrate molar ratio, enzyme dosage, and temperature were examined for yield optimization. Under the optimal conditions, the initial reaction rate and yield of salidroside were as high as 3.04 mM/h and 18.90%, respectively. Moreover, the alcohol acceptor recognition of the enzyme in synthesizing β-D-glucopyranosides was also investigated. The experimental data indicated that β-glycosidase activity and yield varied widely among all the tested alcohols due to the specific spatial structures of various acceptors.
研究领域:
生物化学
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酶工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）