JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
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2016
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IF 2.189
Min Li,Zheng Zhou,Zhi-Jun Zhang,Hui-Lei Yu,Jian-He Xu
Nitrile reductase is a newly discovered enzyme class that can catalyze the reduction of nitriles directly to amines, a very important reaction in synthetic organic chemistry. However, little progress has been made towards the application of this biocatalysis reaction for organic synthesis since the initial discovery of nitrile reductase for over ten years. One of the potential reasons may be due to the lack of structural information and biochemical properties, in addition to its inherent narrow substrate scope. Meanwhile, the highly conserved active site residues make it a great challenge to widen the substrate spectrum of nitrile reductase by means of protein engineering approaches. To explore more nitrile reductases with different characteristics ( e.g . specific activity, thermostability, etc ) for potential synthetic applications, a new nitrile reductase, designated as Pc NRed, was discovered from the genome of Pectobacterium carotovorum , with a moderate specific activity of 366 U/g protein towards its natural substrate, preQ 0 . The Pc NRed was subsequently overexpressed in Escherichia coli BL21 (DE3), purified to homogeneity and then its biochemical properties were examined. The optimal reaction temperature and pH were determined to be 40 °C and 7.4, respectively. The thermal deactivation process of Pc NRed obeys first-order kinetics, with half-lives of 47.2, 13.6 and 3.9 h measured at 30, 40, and 50 °C, respectively. The kinetic constants were also determined with respect to both of the substrates NADPH and preQ 0 , giving k cat of 0.025 s −1 and 0.024 s −1 , and K M of 0.229 mM and <0.25 μM. To shed some light on the structural information of Pc NRed, a homology model was built and compared with its counterparts, which is helpful for further engineering of this novel but less-elucidated enzymes.
研究领域:
生物化学
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酶工程
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合成生物学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2021
·Vol. 10
·期 3
·358-363
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IF 6.331
Ye Yuan,Changyong Gao,Zhexu Wang,Jianming Fan,Haofei Zhou,Daolin Wang,Chang Zhou,Baohua Zhu,Qiang He
We report enzyme-powered upconversion-nanoparticle-functionalized Janus micromotors, which are prepared by immobilizing uricase asymmetrically onto the surface of silicon particles, to actively and rapidly detect uric acid. The asymmetric distribution of uricase on silicon particles allows the Janus micromotors to display efficient motion in urine under the propulsion of biocatalytic decomposition of uric acid and simultaneously detect uric acid based on the luminescence quenching effect of the UCNPs modified on the other side of SiO2. The efficient motion of the motors greatly enhances the interaction between UCNPs and the quenching substrate and improves the uric acid detection efficiency. Overall, such a platform using uric acid simultaneously as the detected substrate and motion fuel offers considerable promise for developing multifunctional micro/nanomotors for a variety of bioassay and biomedical applications.
研究领域:
生物医学工程
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分析化学
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产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
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2022
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IF 6.056
Renjie Zhou,Cheng Yang,Ting Xie,Jian Zhang,Chenqiang Wang,Ziqiang Ma,Lianfu Zhang
Amadori compounds (ACs) are the first stable product formed in the initial stage of the Maillard reaction and are widely present in processed foods. In addition to being widely known as the flavor precursors, ACs have attracted attention in recent years because many functions have been revealed, including ACE inhibition. In this work, we synthesized four ACs ( N -(1-Deoxy-D-fructos-1-yl)-glycine (Fru-Gly), N -(1-Deoxy-D-fructos-1-yl)-proline (Fru-Pro), N -(1-Deoxy-D-fructos-1-yl)-serine (Fru-Ser) and N -(1-Deoxy-D-fructos-1-yl)-threonine (Fru-Thr)) and characterized them using UPLC-Q-TOF-MS spectra. The four ACs’ angiotensin-converting enzyme (ACE) inhibitory activities were verified for the first time, the IC 50 value range was 1.447–4.204 mmol/L, the Fru-Gly has the best effect. And all the four ACs showed good digestion stability, the content remained above 70% after 5 h of continuous digestion simulation. In order to reveal the mechanism of ACs inhibiting ACE, we selected Fru-Gly, beacuse of the best inhibitory effect, to carried out enzyme kinetics, circular dichroism spectroscopy, fluorescence spectroscopy, thermodynamics and molecular docking analysis. The results showed that Fru-Gly was a noncompetitive inhibitor, it spontaneously binds to the inactive site of ACE by hydrogen bond and causes the conformation change of ACE to inactivate it. The reaction is easier to proceed at low temperatures.
研究领域:
食品科学
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生物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
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2019
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IF 2.983
Qingqing Yang,Jing Sun,Chuan Li,Haizhi Zhang,Weiren Xu,Changxiao Liu,Xuemin Zheng
Specific study about the effect of cytochrome P450 2D6 (CYP2D6) polymorphisms on the metabolism of clinic drugs is of great significance for drug safety investigation. Here, the interaction between CYP2D6 variants (*1, *2, *10, *39) and metoprolol (MET) was intensively researched in vitro from the aspect of drug-enzyme kinetic study. To obtain quantitative data, α -hydroxymetoprolol (main metabolite of MET) was selected as an ideal analyte and an LC–MS/MS method was adopted for sample determination. Firstly, by selecting suitable internal standard and optimizing separation condition, the LC–MS/MS method was established and validated. Then, the drug-enzyme incubation system was optimized by two parameters: incubation time and amount of enzyme. Lastly, the interaction between CYP2D6 allelic variants and MET was characterized by K m , V max and CL int . As a result, four CYP2D6 enzymes displayed diverse K m or V max towards MET and the values of CL int showed a wide range from 8.91 to 100%. Relative to CYP2D6*1 (CL int *1 = 100%), CYP2D6*2 demonstrated the second high catalytic activity (CL int *2/*1 = 74.87%) while CYP2D6*39 (CL int *39/*1 = 29.65%) and CYP2D6*10 (CL int *10/*1 = 8.91%) showed minimal catalytic activity. This comprehensive in vitro data suggested the prominent influence of CYP2D6 polymorphisms on the metabolism of MET, which could offer valuable information for personalized administration of MET in clinic.
研究领域:
药理学
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临床医学
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2020
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IF 4.049
Zhao-Yu Wu,Hao Zhang,Yi-Yao Yang,Feng-Qing Yang
In this study, an online capillary electrophoresis (CE) based dual-enzyme (thrombin and factor Xa) co-immobilized microreactor (THR-FXa IMER) was constructed for studying enzyme kinetics and screening dual-target inhibitors against THR and FXa with the aid of the polydopamine/graphene oxide (PDA/GO) coating. Based on the developed THR-FXa IMER, the Michaelis-Menten constants ( K m ) of THR and FXa were calculated to be 187.26 and 48.80 μM, respectively. The inhibition constants ( K i ) for two known inhibitors, argatroban and rivaroxaban, on THR and FXa were determined to be 14.73 and 0.41 nM, respectively. In addition, after 30 consecutive runs, the enzymes’ activity was remained 98% of the initial immobilized activity for both THR and FXa, which shows that the constructed IMER has good stability and repeatability. Finally, the developed method was successfully applied to screen dual-target inhibitors against THR and FXa from 30 small molecular compounds. Among them, 10 compounds such as salvianolic acid C and epigallocatechin gallate (EGCG) have dual-enzyme inhibitory activity, and 2 compounds named saikosaponin A and oleuropein have single THR inhibitory activity, 5 compounds such as rosemary acid and salvianolic acid B have single FXa inhibitory activity. Finally, the molecular interactions between enzyme and potential inhibitors were further verified via the molecular docking, and a new compound with a theoretically good coagulation inhibition effect was designed by the scaffold hopping study. In summary, the developed THR-FXa IMER is a reliable method for screening THR and/or FXa inhibitors.
研究领域:
生物化学
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医学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
·
IF 9.965
Yang Hu,Zixuan Li,Yan Sun
Enzymes that can convert chemical energy into mechanical force through biocatalysis have been used as engines for artificial micro/nanomotors. However, most nanomotors are powered by only one engine and have a microscale size range, which greatly limits their application scenarios. Herein, an ultrasmall enzyme/light-powered nanomotor (71.1 ± 8.2 nm) is prepared by directly coupling ultrasmall histidine-modified Fe 3 O 4 nanoparticles (UHFe 3 O 4 NPs, 2.71 ± 0.54 nm) with cholesterol oxidase (ChOx) for cholesterol detection. The chemical engine, ChOx , catalyzes the oxidation of cholesterol to actuate UHFe 3 O 4 @ChOx and produce H 2 O 2 . Meanwhile, UHFe 3 O 4 NPs that possess peroxidase-mimicking property and photothermal effect act as a nanozyme to catalyze the subsequent chromogenic reaction between H 2 O 2 and 3,3′,5,5′-tetramethylbenzidine for cholesterol detection and simultaneously serve as a photothermal engine power by near-infrared (NIR) irradiation. The nanomotor behavior of UHFe 3 O 4 @ChOx results in an enhancement (55%) of ChOx catalytic efficiency. Moreover, due to the outstanding peroxidase-mimicking activity and cascade reaction, UHFe 3 O 4 @ChOx works as a cholesterol sensor with improved sensitivity and shortened analysis time; as low as 0.178 μM of cholesterol is detected with a linear response range of 2 to 100 μM. Taken together, the new conceptual synthetic strategy of enzymatic hybrid nanomotor is proven promising for sensing and biocatalytic applications.
研究领域:
生物化学
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纳米医学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2021
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IF 6.953
Yan Liu,Chenggang Han,Tao Lu,Yi Liu,Hao Chen,Can Yang,Yanbei Tu,Yanfang Li
Xanthine oxidase (XO) plays a vital role in inducing hyperuricemia and increasing the level of superoxide free radicals in blood, and is proved as an important target for gout. Chrysoeriol (CHE) is a natural flavone with potent XO inhibitory activity (IC 50 = 2.487 ± 0.213 μM), however, the mechanism of interaction is still unclear. Therefore, a comprehensive analysis of the interaction between CHE and XO was accomplished by enzyme kinetics , isothermal titration calorimetry (ITC), multi-spectroscopic methods, molecular simulation and ADMET. The results showed that CHE acted as a rapid reversible and competitive-type XO inhibitor and its binding to XO was driven by hydrogen bonding and hydrophobic interaction. Moreover, CHE exhibited a strong fluorescence quenching effect through a static quenching procedure and induced conformational changes of XO. Its binding pattern with XO was revealed by docking study and the binding affinity to XO was enhanced by the interactions with key amino acid residues in the active pocket of XO. Further, CHE showed good stability and pharmacokinetic behavior properties in molecule dynamic simulation and ADMET prediction. Overall, this study shed some light on the mechanism of interaction between CHE and XO, also provided some valuable information concerning the future therapeutic application of CHE as natural XO inhibitor.
研究领域:
生物化学
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药物化学
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计算生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
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IF 13.2
Liqun Xia,Yi Chen,Haiyang Wu,Mingchao Wang,Gonghui Li
Reaction engineering is key to enhance enzyme-catalyzed reactions. While previous studies have focused on boosting enzyme activity, they often overlook enzyme kinetics—especially the K m ( S 0.5 ) value—that are crucial for optimal performance under physiological conditions. Herein, we developed a novel enzyme-kinetics-guided reaction engineering strategy to improve the substrate affinity of therapeutic enzymes. In this proof-of-concept experiment, we selected arginine deiminase (ADI), a promising therapeutic enzyme for treating arginine-auxotrophic tumors. First, a kinetic trap was identified, and an enzyme-kinetics-based screening model was developed to overcome it. Next, we identified and characterized a novel arginine deiminase (ADI) from Gammaproteobacteria ( Gam ADI), which was subsequently engineered to enhance its catalytic efficiency under the guidance of the kinetic model. Through ultra-high-throughput screening, two ADI variants with low S 0.5 values were identified. After recombination, the final variant GamADI M7 exhibited a remarkable improvement in substrate affinity (91 % reduction in S 0.5 value) and a 1382-fold enhancement in catalytic efficiency. The therapeutic potential of GamADI M7 was validated via cytotoxicity assays in melanoma and prostate cancer cell lines, where its IC 50 values decreased dramatically compared to wild-type ADI. This study highlights the power of enzyme-kinetics-guided reaction engineering, offering a promising strategy to enhance enzyme substrate affinity.
研究领域:
生物化学
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分子生物学
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肿瘤学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2025
·
IF 14.1
Haomiao Bai,Sujun Ding,Yanfei Dai,Jiefu Liu,Huangjing Chen,Wei Feng,Dehong Yu,Yu Chen,Xuejun Ni
Piezoelectric semiconductor nanomaterials have attracted considerable interest in piezocatalytic tumor treatment. However, piezocatalytic therapy encounters obstacles such as suboptimal piezoelectric responses, rapid electron-hole recombination, inefficient energy harvesting, and the complexities of the tumor microenvironment. In this study, sulfur vacancy-engineered cobalt (Co) single-atom doped molybdenum disulfide (SA-Co@MoS 2 ) nanoflowers are strategically designed, which exhibit enhanced piezoelectric effects. Specifically, the introduction of Co single atom not only induces lattice distortion and out-of-plane polarization but also leads to the formation of numerous sulfur vacancies. These changes collectively narrow the intrinsic bandgap of the material, facilitating effective separation and migration of charge carriers, and enabling efficient production of reactive oxygen species under ultrasound stimulation. Additionally, the SA-Co@MoS 2 nanoflowers demonstrate improved enzymatic activity and exhibit glutathione depletion capabilities attributed to the mixed valence states of Co, intensifying oxidative stress in tumor cells, and leading to cell cycle arrest and apoptosis, while the inactivation of glutathione peroxidase 4 induces ferroptosis. Both in vitro and in vivo results indicate that SA-Co@MoS 2 nanoflowers can significantly eliminate tumor cells. This study offers valuable insights into the exploration of single-atom doping-enhanced piezoelectric sonosensitizers for cancer treatment, potentially paving the way for advancements in the field of piezocatalytic synergistic enzyodynamic therapy.
研究领域:
材料科学
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肿瘤学
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纳米医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL BIOCHEMISTRY
·
2017
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IF 2.334
Dong-Mei Liu,Jun-Li Yang,Wei Ha,Juan Chen,Yan-Ping Shi
In the present study, pressure mediated microanalysis (PMMA), a fast, convenient and efficient capillary electrophoresis (CE) method was developed for studying enzyme kinetics of tyrosinase and inhibition kinetics of kojic acid , a model inhibitor of tyrosinase. The enzymatic reaction conditions and CE conditions were optimized in order to obtain high enzyme activity and short analysis time. By PMMA, only the product could be detected at 475 nm, and no voltage was applied to separate the product from the reaction mixture thus greatly simplifying the optimization procedure. The spectrophotometric assay and electrophoretically mediated microanalysis (EMMA) were also performed to validate the developed method. With the present method, the Michaelis-Menten constant ( K m ) was calculated to be 1.347 mM for tyrosinase. The inhibition constant of kojic acid to free tyrosinase ( K I ) and kojic acid to tyrosinase/L-DOPA complex ( K IS ) were calculated to be 36.64 and 74.35 μM, respectively, and the half-maximal inhibitory concentration (IC 50 ) was determined to be 46.64 μM for kojic acid. The developed method is fast and convenient for studying enzyme kinetics, inhibition kinetics and further screening enzyme inhibitors .
研究领域:
生物化学
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Jin Chen,Zhuangwei Zhang,Huihui Li,Hongjin Tang
The control of food browning can be achieved by inhibiting tyrosinase (TY) activity, but current studies on the interaction of flavonoids as potent inhibitors with TY are inadequate. Herein, the effect of a library of flavonoids on TY was investigated using enzyme kinetics , multispectroscopic methods, and molecular modelling. Some flavonoids including 4 , 8 , 10 , 17 , 18 , 28 , 30 , 33 , and 34 exhibited potent TY inhibitory activity, with compound 10 demonstrating reversible inhibition in a mixed-competitive manner. Ultraviolet-visible spectral changes confirmed the formation of flavonoid-TY complexes. Fluorescence quenching analysis suggested effective intrinsic fluorescence quenching by flavonoids through static quenching with the ground-state complex formation. Synchronous fluorescence spectra showed the microenvironment change around the fluorophores induced by flavonoids. ANS-binding fluorescence assay indicated TY's surface hydrophobicity change by flavonoids and highlighted the change in secondary structure conformation, which was further confirmed by Fourier-transform infrared spectra. Molecular modelling results helped visualize the preferred binding conformation at the active site of TY, and demonstrated the important role of hydrophobic interaction and hydrogen bonding in stabilizing the flavonoid-TY complexes. These findings prove that diverse flavonoid structures distinctly impact their binding behavior on TY and contribute to understanding flavonoids' potential as TY inhibitors in controlling food browning.
研究领域:
食品科学
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生物化学
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药物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CONTROLLED RELEASE
·
2024
·
IF 10.5
Haixin Tan,Ziwei Hu,Jiajun Miao,Bin Chen,Huaan Li,Junbin Gao,Yicheng Ye,Wenxin Xu,Jiamiao Jiang,Hanfeng Qin,Hao Tian,Fei Peng,Yingfeng Tu
The development of an intelligent nanomotor system holds great promise for enhancing the efficiency and effectiveness of antitumor therapy. Leveraging the overexpressed substances in the tumor microenvironment as propellants and chemotactic factors for enzyme-powered nanomotors represents a versatile and compelling approach. Herein, a plasma amine oxidase (PAO)-based chemotactic nanomotor system has been successfully developed, with the ability to enzymatically produce toxic acrolein and H 2 O 2 from the upregulated polyamines (PAs) in the tumor microenvironment for active tumor therapy. Zwitterionic polymeric nanoparticles with superior biocompatibility are synthesized, followed by PAO modification via electrostatic interactions. As expected, the resulting nanomotor system exhibits positive chemotaxis toward PAs concentration gradient. Upon reaching the tumor region, our nanomotors, actuated by the tumor microenvironmental PAs, effectively enhance diffusion and enable deep penetration into the tumor site. This leads to the induction of tumor apoptosis and simultaneous inhibition of tumor invasion and migration by decomposing PAs into toxic products. By smartly utilizing the consumption of these local chemotactic factors and their enzymatic products, our nanomotor system provides a versatile and intelligent platform for active and enhanced tumor therapy.
研究领域:
生物医学工程
·
肿瘤学
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纳米医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）