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Cloning and Functional Analysis of a cDNA Encoding Ginkgo biloba Farnesyl Diphosphate Synthase
Kexuan Tang,Peng Wang,Zhihua Liao,Liang Guo,Wenchao Li,Min Chen,Yan Pi,Yifu Gong,Xiaofen Sun 한국분자세포생물학회 2004 Molecules and cells Vol.18 No.2
Farnesyl diphosphate synthase (FPS; EC2.5.1.1/EC2. 5.1.10) catalyzes the synthesis of farnesyl diphosphate, and provides precursor for biosynthesis of sesquiterpene and isoprenoids containing more than 15 isoprene units in Ginkgo biloba. Here we report the cloning, characterization and functional analysis of a new cDNA encoding FPS from G. biloba. The full-length cDNA (designated GbFPS) had 1731 bp with an open reading frame of 1170 bp encoding a polypeptide of 390 amino acids. The deduced GbFPS was similar to other known FPSs and contained all the conserved regions of trans-prenyl chain-elongating enzymes. Structural modeling showed that GbFPS had the typical structure of FPS, the most prominent feature of which is the arrangement of 13 core helices around a large central cavity. Southern blot analysis revealed a small FPS gene family in G. biloba. Expression analysis indicated that GbFPS expression was high in roots and leaves, and low in stems. Functional complementation of GbFPS in an FPS-deficient strain confirmed that GbFPS mediates farnesyl diphosphate biosynthesis.
Feiyan Chen,Kexuan Zhu,Lin Chen,Liufeng Ouyang,Cuihua Chen,Ling Gu,Yucui Jiang,Zhongli Wang,Zixuan Lin,Qiang Zhang,Xiao Shao,Jianguo Dai,Yunan Zhao 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.3
Background: Ginseng effectively reduces fatigue in both animal models and clinical trials. However, themechanism of action is not completely understood, and its molecular targets remain largely unknown. Methods: By screening for proteins that interact with the primary components of ginseng (ginsenosides)in an affinity chromatography assay, we have identified muscle-type creatine kinase (CK-MM) as a potentialtarget in skeletal muscle tissues. Results: Biolayer interferometry analysis showed that ginsenoside metabolites, instead of parent ginsenosides,had direct interaction with recombinant human CK-MM. Subsequently, 20(S)-protopanaxadiol(PPD), which is a ginsenoside metabolite and displayed the strongest interaction with CK-MM in thestudy, was selected as a representative to confirm direct binding and its biological importance. Biolayerinterferometry kinetics analysis and isothermal titration calorimetry assay demonstrated that PPDspecifically bound to human CK-MM. Moreover, the mutation of key amino acids predicted by moleculardocking decreased the affinity between PPD and CK-MM. The direct binding activated CK-MM activityin vitro and in vivo, which increased the levels of tissue phosphocreatine and strengthened the functionof the creatine kinase/phosphocreatine system in skeletal muscle, thus buffering cellular ATP, delayingexercise-induced lactate accumulation, and improving exercise performance in mice. Conclusion: Our results suggest a cellular target and an initiating molecular event by which ginsengreduces fatigue. All these findings indicate PPD as a small molecular activator of CK-MM, which can helpin further developing better CK-MM activators based on the dammarane-type triterpenoid structure.
Linfei Xia,Qingfeng Wu,Kexuan Zhou,Bin Han,Feng He,Zhijun Wang 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.12
According to the precipitation and recrystallization behavior, the precipitation and recrystallization can be concurrently tunedtoward the excellent mechanical property. In this study, a synergistically strengthened Co37Cr20Ni37Ti3Al3 high-entropyalloy was developed through concurrent recrystallization and precipitation (CRP) approach. After the treatment, the highdensityγ' precipitates were introduced in the matrix, while the fully-recrystallized ultrafine grains and annealing twins wereobtained from the recrystallization. Compared with conventional treatment, the CRP-HEA exhibits a superior combinationof ~ 1.62GPa tensile strength and ~ 28% elongation, which is attributed to the synergistic strengthening of precipitation andgrain boundary. In addition, the deformation mechanisms were characterized by TEM. The cutting-through mechanismdominates the deformation behaviors. Moreover, interesting stacking faults in different slip planes prevail during plasticdeformation. The concurrent recrystallization and precipitation for ultra-fine grain structure with nano-precipitates wouldprovide an effective strategy to achieve outstanding combination of strength and ductility.
Chen, Feiyan,Zhu, Kexuan,Chen, Lin,Ouyang, Liufeng,Chen, Cuihua,Gu, Ling,Jiang, Yucui,Wang, Zhongli,Lin, Zixuan,Zhang, Qiang,Shao, Xiao,Dai, Jianguo,Zhao, Yunan The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.3
Background: Ginseng effectively reduces fatigue in both animal models and clinical trials. However, the mechanism of action is not completely understood, and its molecular targets remain largely unknown. Methods: By screening for proteins that interact with the primary components of ginseng (ginsenosides) in an affinity chromatography assay, we have identified muscle-type creatine kinase (CK-MM) as a potential target in skeletal muscle tissues. Results: Biolayer interferometry analysis showed that ginsenoside metabolites, instead of parent ginsenosides, had direct interaction with recombinant human CK-MM. Subsequently, 20(S)-protopanaxadiol (PPD), which is a ginsenoside metabolite and displayed the strongest interaction with CK-MM in the study, was selected as a representative to confirm direct binding and its biological importance. Biolayer interferometry kinetics analysis and isothermal titration calorimetry assay demonstrated that PPD specifically bound to human CK-MM. Moreover, the mutation of key amino acids predicted by molecular docking decreased the affinity between PPD and CK-MM. The direct binding activated CK-MM activity in vitro and in vivo, which increased the levels of tissue phosphocreatine and strengthened the function of the creatine kinase/phosphocreatine system in skeletal muscle, thus buffering cellular ATP, delaying exercise-induced lactate accumulation, and improving exercise performance in mice. Conclusion: Our results suggest a cellular target and an initiating molecular event by which ginseng reduces fatigue. All these findings indicate PPD as a small molecular activator of CK-MM, which can help in further developing better CK-MM activators based on the dammarane-type triterpenoid structure.
Wang, Yechun,Guo, Binhui,Zhang, Fei,Yao, Hongyan,Miao, Zhiqi,Tang, Kexuan Korean Society for Biochemistry and Molecular Biol 2007 Journal of biochemistry and molecular biology Vol.40 No.6
The enzyme 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR; EC1.1.1.34) catalyzes the first committed step of isoprenoids biosynthesis in MVA pathway. Here we report for the first time the cloning and characterization of a full-length cDNA encoding HMGR (designated as CgHMGR, GenBank accession number EF206343) from hazel (Corylus avellana L. Gasaway), a taxol-producing plant species. The full-length cDNA of CgHMGR was 2064 bp containing a 1704-bp ORF encoding 567 amino acids. Bioinformatic analyses revealed that the deduced CgHMGR had extensive homology with other plant HMGRs and contained two transmembrane domains and a catalytic domain. The predicted 3-D model of CgHMGR had a typical spatial structure of HMGRs. Southern blot analysis indicated that CgHMGR belonged to a small gene family. Expression analysis revealed that CgHMGR expressed high in roots, and low in leaves and stems, and the expression of CgHMGR could be up-regulated by methyl jasmonate (MeJA). The functional color assay in Escherichia coli showed that CgHMGR could accelerate the biosynthesis of $\beta$-carotene, indicating that CgHMGR encoded a functional protein. The cloning, characterization and functional analysis of CgHMGR gene will enable us to further understand the role of CgHMGR involved in taxol biosynthetic pathway in C. avellana at molecular level.
Rational design of porous NiCo2S4 nanotubes for hybrid supercapacitor
Wang Haiyang,Liang Miaomiao,He Zemin,Guo Zhun,Zhao Yang,Li Kexuan,Song Wenqi,Zhang Yongming,Zhang Xin,Zhao Yuzhen,Miao Zongcheng 한국물리학회 2022 Current Applied Physics Vol.35 No.-
The nanotube-consisted flower-like NiCo2S4 is successfully fabricated by a novel two-step hydrothermal technique. X-ray diffraction (XRD) identifies the spinel structure, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) imply the flower-like morphology of the synthesized NiCo2S4. The electrochemical behaviors are studied by cyclic voltammetry and galvanostatic charge-discharge measurements. The NiCo2S4 nanotubes demonstrate enhanced pseudocapacitive performance of 429.5 C g− 1 at current density of 0.5 A g− 1 . The NiCo2S4//AC device delivers high energy density of 37.69 Wh kg− 1 , maximum power density of 4000.6 W kg− 1 and satisfied cycle property of 96% capacitance retention after over 7000 cycles. The results show that the NiCo2S4 nanotubes are promising electrode material for high performance supercapacitor applications.
Metabolic Engineering of Vitamin C Production in Arabidops
Ling Xiao,Ying Xiao,Zinan Wang,Hexin Tan,Kexuan Tang,Lei Zhang 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.4
Vitamin C (L-ascorbic acid, AsA) is a compound which provides major nutritional value, both for plants and humans. In this study, three distinct metabolic engineering strategies, including overexpression of biosynthesis enzyme, suppression of catabolism enzyme and switching the sub-cellular localization of compartment enzyme, were employed to enhance the production of AsA in Arabidopsis thaliana. The results showed that (1) overexpression of L-Galactose-1-P Phosphatase (GalPPase) enhanced AsA content to 3.96 μmol/g FW, which was 1.6-fold more than that in their wild-type (WT) counterparts; (2) RNAi suppression of ascorbate oxidase (AO) resulted in a significant increase of AsA accumulation (0.86 μmol/g FW) in apoplast; (3) both mitochondrion-target and none-target overexpression of L-Galactose dehydrogenase (GalDH) did not significantly promote AsA production compared with WT (1.96 μmol/g), however a dramatic enhancement was observed following infiltration with L-galactono-1, 4-lactone (L-GalL), both in transgenic and WT plants. The best line produced AsA with the content of 3.90 μmol/g FW, which was about 2-fold of that in the untreated control (1.99 μmol/g FW). This study provides new strategies including GalPPase overexpression, AO suppression as well as L-GalL feeding for modern breeding aimed at stimulating the AsA content in plants.
Huang, Zhuoshi,Jiang, Keji,Pi, Yan,Hou, Rong,Liao, Zhihua,Cao, Ying,Han, Xu,Wang, Qian,Sun, Xiaofen,Tang, Kexuan Korean Society for Biochemistry and Molecular Biol 2007 Journal of biochemistry and molecular biology Vol.40 No.5
The enzyme squalene synthase (EC 2.5.1.21) catalyzes a reductive dimerization of two farnesyl diphosphate (FPP) molecules into squalene, a key precursor for the sterol and triterpene biosynthesis. A full-length cDNA encoding squalene synthase (designated as TcSqS) was isolated from Taxus cuspidata, a kind of important medicinal plants producing potent anti-cancer drug, taxol. The full-length cDNA of TcSqS was 1765 bp and contained a 1230 bp open reading frame (ORF) encoding a polypeptide of 409 amino acids. Bioinformatic analysis revealed that the deduced TcSqS protein had high similarity with other plant squalene synthases and a predicted crystal structure similar to other class I isoprenoid biosynthetic enzymes. Southern blot analysis revealed that there was one copy of TcSqS gene in the genome of T. cuspidata. Semi-quantitative RT-PCR analysis and northern blotting analysis showed that TcSqS expressed constitutively in all tested tissues, with the highest expression in roots. The promoter region of TcSqS was also isolated by genomic walking and analysis showed that several cis-acting elements were present in the promoter region. The results of treatment experiments by different signaling components including methyl-jasmonate, salicylic acid and gibberellin revealed that the TcSqS expression level of treated cells had a prominent diversity to that of control, which was consistent with the prediction results of TcSqS promoter region in the PlantCARE database.