Molecular Catalysis
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2024
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IF 3.9
Yuqiu Wu,Fanjin Meng,Jiaolong Fu,Yuyang Zhou,Huan Fan,Xin Ju,Liangzhi Li
D-xylose, a biomass derivative, is used as a substrate to generate D-xylulose and D-ribulose with high-added value through a cascade reaction. During this process, the thermal stability and catalytic efficiency of rate-limiting enzymes during cascade reactions are important issues that must be addressed in industrial applications. In this study, we prepared and validated PDA/SiO 2 microspheres as highly loaded immobilization carriers by oxidative self-polymerization of polydopamine (PDA) on silica (SiO 2 ) microspheres. D-xylose was successfully catalyzed by the co-immobilized D-5-phosphate ribose isomerase B (RpiB) and D-tagatose-3-epimerase (DTE), denoted PDA/SiO 2 -RpiB-DTE, to produce D-ribulose and D-xylulose. After immobilization, the K m of co-immobilized RpiB and DTE decreased, which suggested increased substrate affinity. The half-life of the co-immobilized enzymes was 3.5–8 fold higher than that of the free enzymes at 50–70 °C, and the inactivation rate constant was reduced, demonstrating that immobilization improved significantly the thermal stability. The conversion of D-xylose at 10 mM was 29.98% under optimal conditions, which contained 9.85% D-ribulose and 20.13% D-xylulose. PDA/SiO 2 -RpiB-DTE showed up to 89.10% initial enzyme activity after 3 recycle runs. The thermal stability and recovery aspects were improved by immobilization, which facilitates the use of biomass to produce high-value-added products and further exploitation.
研究领域:
生物技术
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酶工程
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生化工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2021
·
IF 4.311
Xiaoyan Chen,Fan Wang,Qiang Yu,Shijie Liu,Wen Wang,Yu Zhang,Zhongming Wang,Zhenhong Yuan
One pot cascade of enzymatic catalysis was applied for d -allulose synthesis from d -glucose by the combination of d -glucose isomerase (GI) from Escherichia coli MG1655 and d -allulose 3-epimerase (DAE) from Agrobacterium tumefaciens C58. The synthesis process was investigated by characterizing the initial substrate concentration, molar ratios of GI and DAE, the enzyme loading, and contents of cobalt and magnesium ions. The increase of enzyme loading and the molar ratios of GI vs DAE caused the raising of d -allulose yield from 4% to 9%, verifying that the generation rate of d -fructose was an essential factor for rare sugar conversion improvement. The optimal enzyme loadings required for reactions with substrate concentrations of 100 g L −1 and 200 g L −1 were 60 U and 200 U. Kinetics stimulation was conducted to reveal the underlying relationship within the three sugars converted by dual-enzyme, with the fitting curve validated the reliability of the model.
研究领域:
生物化学
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酶工程
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食品科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
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2014
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IF 1.552
Xingcui Guo,Xicheng Wang,Jing Guan,Xiufang Chen,Zhangfeng Qin,Xindong Mu,Mo Xian
Ru particles were introduced into the zeolite ZSM-5 (MFI) by either a conventional impregnation method or a one-step template-free process. The resultant materials were characterized by X-ray diffraction, N 2 adsorption-desorption, scanning electron microscopy, transmission electron microscopy, NH 3 and CO 2 temperature-programmed desorption. The results indicated that the Ru species in ZSM-5 catalysts prepared via the latter approach (designated as Ru/ZSM-5-TF) were highly dispersed in the ZSM-5 framework structure and this material exhibited high catalytic performance during the hydrogenation of D-glucose to D-sorbitol. The conversion of D-glucose was as high as 99.6% with D-sorbitol selectivity reaching 99.2%, exceeding the performance of Ru/ZSM-5 catalysts prepared by the conventional impregnation method with microporous or desilicated ZSM-5 supports. More importantly, this catalyst showed high stability against leaching and poisoning and could be reused several times. The extensive dispersion of the Ru species, strong interaction between the Ru species and the ZSM-5, and the suitable surface acidity-basicity balance of the Ru/ZSM-5-TF were all critical factors leading to excellent catalytic behavior and stability.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
Theranostics
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2018
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IF 8.537
Xinglong Yang,Yan Dang,Jinli Lou,Huawu Shao,Xingyu Jiang
Rationale: Rapid and facile detection of pathogenic bacteria is challenging due to the requirement of large-scale instruments and equipment in conventional methods. We utilize D-amino acid as molecules to selectively target bacteria because bacteria can incorporate DADA in its cell wall while mammalian cells or fungi cannot. Methods: We show a broad-spectrum bacterial detection system based on D-amino acid-capped gold nanoparticles (AuNPs). AuNPs serve as the signal output that we can monitor without relying on any complex instruments. Results: In the presence of bacteria, the AuNPs aggregate and the color of AuNPs changes from red to blue. This convenient color change can distinguish between Staphylococcus aureus ( S. aureus ) and methicillin-resistant Staphylococcus aureus (MRSA). This system can be applied for detection of ascites samples from patients. Conclusion: These D-amino acid-modified AuNPs serve as a promising platform for rapid visual identification of pathogens in the clinic.
研究领域:
生物医学工程
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2019
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IF 6.393
Han Liu,Juanjuan Shao,Lixia Shi,Wei Ke,Fangjie Zheng,Yuan Zhao
A simple and accurate magnetic electrochemical sensor is developed for the ultrasensitive chiral recognition of D-amino acids (D-AAs). Fe 3 O 4 @Au@Ag@Cu x O nanoparticles (NPs) (x = 1, 2) are controllable prepared and used as the electrochemical beacons. The controllable integration of plasmonic metal NPs, semiconductors and magnetic NPs enables multilayered Fe 3 O 4 @Au@Ag@Cu x O NPs to display a sharp copper stripping peak at -0.16 V, owning to the electron transfer from Cu + to Cu 2+ and the synergistic electron transfer of Au and Ag double layers. D-AAs can be catalyzed by D-amino acid oxidase (DAAO) to produce H 2 O 2 . The autocatalytic oxidation reaction of Cu x O shell with the existence of H 2 O 2 induces the decrease of electrochemical signals of Fe 3 O 4 @Au@Ag@Cu x O NPs. Fe 3 O 4 @Au@Ag@Cu x O NPs served as electrochemical beacons achieve the sensitive and accurate enantioselective recognition of D-alanine (D-Ala) in the range from 100 pM to 10 μM. The limit of detection (LOD) is as low as 52 pM. This developed protocol can be extended to the fabrication of a large set of electroactive labels by the introduction of plasmonic metal NPs with high electron transfer efficiency, for the reliable enantioselective recognition with high sensitivity.
研究领域:
生物化学
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分析化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2022
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IF 3.662
Yongliang Liu,Shengbo Zhu,Yilin Su,Ran Chen,Wenzhi Zhang,Xiaoling Niu,Weixing Chen,Xinbing Chen,Zhongwei An
Three new D-π-D thiophene derivatives ( TPAThTPA , TPAThThTPA , and TPATTTPA ) are synthesized and employed to fabricate the solution-typed electrochromic devices . Density functional theory (DFT) calculation, electrochemical and photophysical characterization is carried out to study their electrochromic performances. When the applied voltage is conducted, the UV–vis absorption wavelength does not shift, but the absorbance increases significantly, accompanied by electrochromic behaviors. After removing the applied voltage, the self-bleaching phenomenon occurs. In addition, electrochromic devices based on these three D-π-D thiophene derivative solutions are fabricated by a simple process. In a word, this research provides a feasible method for developing new electrochromic materials and devices.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
Frontiers in Bioengineering and Biotechnology
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2022
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IF 6.064
Wang Jing,Chen Qiaoyu,Wang Xin,Chen Kequan,Ouyang Pingkai
D-1,2,4-Butanetriol (BT) has attracted much attention for its various applications in energetic materials and the pharmaceutical industry. Here, a synthetic pathway for the biosynthesis of BT from d-arabinose was constructed and optimized in Escherichia coli. First, E. coli Trans1-T1 was selected for the synthesis of BT. Considering the different performance of the enzymes from different organisms when expressed in E. coli, the synthetic pathway was optimized. After screening two d-arabinose dehydrogenases (ARAs), two d-arabinonate dehydratases (ADs), four 2-keto acid decarboxylases (ADXs), and three aldehyde reductases (ALRs), ADG from Burkholderia sp., AraD from Sulfolobus solfataricus, KivD from Lactococcus lactis IFPL730, and AdhP from E. coli were selected for the bio-production of BT. After 48 h of catalysis, 0.88 g/L BT was produced by the recombinant strain BT5. Once the enzymes were selected for the pathway, metabolic engineering strategy was conducted for further improvement. The final strain BT5ΔyiaEΔycdWΔyagE produced 1.13 g/L BT after catalyzing for 48 h. Finally, the fermentation conditions and characteristics of BT5ΔyiaEΔycdWΔyagE were also evaluated, and then 2.24 g/L BT was obtained after 48 h of catalysis under the optimized conditions. Our work was the first report on the biosynthesis of BT from d-arabinose which provided a potential for the large-scale production of d-glucose-based BT.
研究领域:
生物化学
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微生物学
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合成生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry C
·
2024
·
IF 3.3
Zhi-Qiang Wang,Wanjun Guo,Shengchao Jia,Yaxuan Jing,Shiting Li,Yong Guo,Xiaohui Liu,Xue-Qing Gong,Yanqin Wang
The selective production of primary amines through reductive amination has received increasing attention due to their extensive applications, while efficient reductive amination is still challenging. Herein, a novel strategy was developed to realize the efficient reductive amination of carbonyl compounds with NH3 via d–d orbital coupling strategies in RuCo alloys. The designed series of RuCo alloy catalysts not only exhibited excellent performance in conversion of various substrates but also demonstrated universal applicability across different supports. The key role of RuCo alloy is its unique ability to effectively catalyze the ammonolysis of a Schiff base, the rate-determining step in reductive amination. Theoretical studies reveal that the d–d orbital coupling strategies break the five d orbital equivalent contributions of metal (Co or Ru) atoms, and the d orbitals primarily contribute through the dz2 and dx2-y2 orbitals of Ru and the dz2 orbital of Co on the RuCo(001) surface, which significantly driving the homolytic NH3 dissociation during the ammonolysis of the Schiff base. Furthermore, stable Co–H covalent bond species and RuCo-NH2 half-ionic and half-covalent bond species on the RuCo(001) surface were generated with lower energy levels. This work not only achieves efficient reductive amination but also provides an atomic orbital-level understanding of the d–d orbital coupling strategies for heterogeneous catalysis.
研究领域:
催化化学
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材料科学
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理论化学
✓ 已验证
产品关联
DOI
高影响因子
Systems Microbiology and Biomanufacturing
·
2023
·
IF 0
Zhang Landong,Gao Changzheng,Song Wei,Wei Wanqing,Gao Cong,Chen Xiulai,Liu Jia,Liu Liming,Wu Jing
D -p -hydroxyphenylglycine (D-HPG) is an important intermediate in the pharmaceutical industry, and it is commonly synthesized by cascading D-hydantoinase (DHase) and D-carbamoylase (DCase). In this study, the stability of DCase was identified as the main problem that limits its application. Therefore, the complexed structure of Ak DCase (DCase from the Agrobacterium sp . strain KNK712) with the substrate N-carbamoyl-D- p -hydroxyphenylglycine (C p HPG) (with 2.52 Å resolution) and catalytic mechanism were resolved. Based on the catalytic mechanism and electrostatic stabilization, salt bridge engineering was adopted to improve Ak DCase thermostability. The best variant, Ak DCase D30A , increased the T m by 2.91 °C and half-life (t 1/2 ) at 40 and 60 °C by 18.43 h and 23.21 min, respectively. After Ak DCase D30A was assembled with Gs DHase (DHase from Geobacillus stearothermophilus SD-1) in a single Escherichia coli cell, the recombinant strain could produce 29.53 g/L D-HPG within 12 h, with a 97% conversion and a 2.46 g/(L·h) space–time yield (STY). The titer of D-HPG increased by 40.55% compared to the E. coli cell harboring pETduet-1- Ak DCase- Gs DHase. The recombinant strain could be used for two cycles. Our research provides a basis for the industrial production of D-HPG.
研究领域:
生物催化
·
蛋白质工程
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工业微生物学
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结构生物学
✓ 已验证
DOI
FOOD CHEMISTRY
·
2016
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IF 4.052
Baogang Xie,Yalan Liu,Huiqin Zou,Yong Son,Huiyun Wang,Haipeng Wang,Jianghua Shao
d -Glucaric acid (GA) derivatives exhibit anti-cancerogenic properties in vivo in apples, but quantitative information about these derivatives is limited. Hydrophilic interaction-based HPLC with ultraviolet detection or mass spectrometry was developed to quantify GA and/or d -glucaro-1,4-lacton (1,4-GL) in apples. Although the formation of 1,4-GL from GA could be the prerequisite to exert biological effects in vivo , only a small portion of GA (<5%) was identified and converted to 1,4-GL in the rat stomach. The 1,4-GL content in apples ranged from 0.3 mg/g to 0.9 mg/g, and this amount can substantiate health claims associated with apples. The amount of 1,4-GL was 1.5 times higher in Gala and the ratio of 1,4-GL to GA was lower in Green Delicious apples than those in the other varieties. Our findings suggested that the variety and maturity of apples at harvest are factors that determine 1,4-GL content.
研究领域:
食品科学
·
植物化学
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营养学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2025
·
IF 6.2
Xinrui Tang,Abdullah Arsalan,Guoyan Zhang,Junhua Yun,Cunsheng Zhang,Xianghui Qi
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 Blautia produca D-allulose 3-epimerase (Bp-DAE) and Bacillus subtilis L-rhamnose isomerase (BsL-RI) within a single cell using B. subtilis WB800N as the host. Using this system, D-allose was synthesized via a simple, cost-effective, one-pot enzymatic process, employing whole cells as catalysts and D-fructose as the substrate. The system exhibited optimal activity at 65 °C, pH 8.5, with 1 mM Mn2+ and 20 g/L of whole-cell dry weight. Initial production reached 12.5 g/L D-allose with a 12.5% yield from 100 g/L D-fructose. Optimization of dual promoter combinations enhanced production, achieving 15.0, 29.1, and 43.2 g/L D-allose from 100, 200, and 300 g/L D-fructose, with yields of 15.00, 14.55, and 14.40%, respectively. This D-allose production biocatalyst offers a scalable and economically viable platform for the industrial production of rare sugar.
研究领域:
生物化学
·
食品科学
·
工业微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2019
·
IF 9.518
Tingting Tian,Mingxia Liu,Lixia Chen,Fengjiao Zhang,Xin Yao,Hong Zhao,Xiangjun Li
For D-amino acid (DAA) electrochemical biosensors , it is necessary to achieve chiral recognition in racemic solutions or mixtures. However, common chiral recognition is only performed in a single isomer solution. Here, D-amino acid oxidase (DAAO) was used as a chiral selector, and carbon nanotubes (CNTs) as a signal amplifier to construct a non-mediator-style DAA biosensor. The biosensor showed high performance against enantiomer interference: in alanine (Ala) enantiomer mixtures, accurate quantification of D-Ala was achieved when the concentration ratio of L-Ala to D-Ala was 100. In Ala racemic solutions, the linear equation slope was almost consistent with that of standard D-Ala. This high performance was due to the combination of stereoselectivity (enzyme protein) and a catalytic reaction (redox center). The mechanism for the electrical signal change of the biosensor was explored and verified by cyclic voltammetry (CV). The results showed that (i) flavin adenine dinucleotide (FAD, redox center of DAAO) was a direct electroactive substance that produced a reduction peak current; in the presence of O 2 , the amount of FAD increased leading to an increase of the reduction peak current. (ii) In the presence of DAA, the chemical reaction FAD + DAA → imino acids + FADH 2 occurred and consumed FAD, which resulted in its decrease; thus, the reduction peak current also decreased. Under the same oxygen concentration, the linear decrease of the reduction peak current in the presence of DAA was due to FAD consumption. The biosensor was used for practical analyses in milk and urine samples with satisfactory results.
研究领域:
生物化学
·
分析化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）