CATALYSIS LETTERS
·
2018
·Vol. 148
·期 6
·1714-1722
·
IF 2.911
Luo Wei,Deng Xin-Xing,Huo Jiao,Ruan Tao,Gong Zhi-Wei,Yan Jia-Bao,Yang Zhong-Hua,Quan Can,Cui Zhi-Fang
Abstract Microalgae are excellent biocatalyst candidates for photo-biocatalytic-asymmetric reduction of prochiral ketones to produce enantiomer alcohols. In the biocatalysis asymmetric reduction of carbonyl group process, the cofactor, NADPH, plays a key role. So the current study focused on the effect of NADPH availability on the reduction. Photosynthesis is a main pathway for NADPH regeneration in microalgae, and the ferredoxin-NADP + oxidoreductase (FNR) is the key enzyme in this process. In this work, we constructed an engineered cyanobacterium Synechocystis sp. PCC6803:: Ω- P petE-petH to overexpress FNR gene petH to strengthen NADPH regeneration. The results show that the intracellular NADPH content was increased 80.8% compared to the wild type. Applying the Synechocystis sp. PCC6803:: Ω- P petE-petH to catalyze the model asymmetric reduction reaction (reduction of acetophenone to S -phenylethanol), the yield was improved 61.2% compared to the wild-type. This work makes the microalgal biocatalysis asymmetric reduction process become more preponderant via providing a new route to enhance the regeneration of cofactor NADPH. Graphical Abstract Putative metabolic process of nicotinamide adenine dinucleotide phosphate (NADPH) regeneration and the photo-biocatalytic-asymmetric reduction reaction of prochiral ketones in microalgal cells.
研究领域:
生物化学
·
合成生物学
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DOI
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2015
·Vol. 99
·期 11
·4629-4643
·
IF 3.337
Zhang Yan,Shi Junling,Gao Zhenhong,Yangwu Ruiming,Jiang Huanshi,Che Jinxin,Liu Yanlin
Phomopsis sp. XP-8 is an endophytic fungus that has the ability to produce pinoresinol diglucoside (PDG) in vitro and thus has potential application for the biosynthesis of PDG independent of plants. When cultivated in mung bean medium, PDG production was significantly improved and pinoresinol monoglucoside (PMG) and pinoresinol (Pin) were also found in the culture medium. In this experiment, starch, protein, and polysaccharides were isolated from mung beans and separately used as the sole substrate in order to explore the mechanism of fermentation and identify the major substrates that attributed to the biotransformation of PDG, PMG, and Pin. The production of PDG, PMG, and Pin was monitored using high-performance liquid chromatography (HPLC) and confirmed using HPLC-MS. Activities of related enzymes, including phenylalanine ammonia-lyase (PAL), trans-cinnamate 4-hydroxylase (C4H), and 4-coumarate-CoA ligase (4CL) were analyzed and tracked during the cultivation. The reaction system contained the compounds isolated from mung bean in the designed amount. Accumulation of phenylalanine, cinnamic acid, p-coumaric acid, PDG, PMG, and Pin and the activities of PAL, C4H, and 4CL were measured during the bioconversion. PMG was found only when mung bean polysaccharide was analyzed, while production of PDG and Pin were found when both polysaccharide and starch were analyzed. After examining the monosaccharide composition of the mung bean polysaccharide and the effect of the different monosaccharides had on the production of PMG, PDG, and Pin, galactose in mung bean polysaccharide proved to be the major factor that stimulates the production of PMG.
研究领域:
微生物学
·
生物化学
·
天然产物化学
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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
·
酶学
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工业发酵
✓ 已验证
DOI
PubMed
高影响因子
Scientific Reports
·
2019
·Vol. 9
·期 1
·1-13
·
IF 4.011
Xu Shuwen,Wang Gang,Peng Wei,Xu Yandi,Zhang Yu,Ge Ying,Jing Yue,Gong Zhunan
Type 2 diabetes (T2D) with high morbidity and mortality is characterized by abnormal glucose and lipid metabolism due in part to insulin resistance in liver, which lead to elevated hyperglycemia and hyperlipidemia. This study sough to explore the effects of corosolic acid (CA) in different T2D models and explored the underlying mechanism. Separated from Eriobotrya japonica leaves, CA purity was above 95% measured by a HPLC method. Compared with cAMP and DEX induced T2D HepG2 model, CA significantly stimulated glucose consumption and improved glycogen accumulation by inhibiting PEPCK mRNA expression. And in cAMP and DEX induced T2D zebrafish model, CA reduced glycogen degradation and increased glucose consumption by regulating some key enzymes in carbon metabolism including GLUT1, GLUT2, GLUT3, LDHA, LDHB, GP, G6Pase, GYS1, and PFKFB3. In addition, insulin receptor signals were also involved in CA-regulated hypoglycemic action. Furthermore, in STZ-induced T2D rat model, compared with diabetic control groups, CA remarkably downregulated the levels of serum lipid, blood glucose, ICAM-1, malonaldehyde and insulin resistance index, while upregulated SOD activity and impaired glucose tolerance. In a conclusion, CA can regulate glucose and lipid metabolic adaptation in T2D like HepG2, zebrafish and rat models partly through reducing inflammation and oxidative stress and suppressing PEPCK .
研究领域:
药理学
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糖尿病研究
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分子生物学
✓ 已验证
DOI
PubMed
高影响因子
Nature Communications
·
2019
·Vol. 10
·期 1
·1-11
·
IF 11.878
Hong Yi,Zhou Feifei,Hua Yujie,Zhang Xianzhu,Ni Chengyao,Pan Dihao,Zhang Yiqing,Jiang Deming,Yang Long,Lin Qiuning,Zou Yiwei,Yu Dongsheng,Arnot David E.,Zou Xiaohui,Zhu Linyong,Zhang Shufang,Ouyang Hongwei
Uncontrollable bleeding is a major problem in surgical procedures and after major trauma. Existing hemostatic agents poorly control hemorrhaging from traumatic arterial and cardiac wounds because of their weak adhesion to wet and mobile tissues. Here we design a photo-reactive adhesive that mimics the extracellular matrix (ECM) composition. This biomacromolecule-based matrix hydrogel can undergo rapid gelling and fixation to adhere and seal bleeding arteries and cardiac walls after UV light irradiation. These repairs can withstand up to 290 mm Hg blood pressure, significantly higher than blood pressures in most clinical settings (systolic BP 60–160 mm Hg). Most importantly, the hydrogel can stop high-pressure bleeding from pig carotid arteries with 4~ 5 mm-long incision wounds and from pig hearts with 6 mm diameter cardiac penetration holes. Treated pigs survived after hemostatic treatments with this hydrogel, which is well-tolerated and appears to offer significant clinical advantage as a traumatic wound sealant.
研究领域:
生物材料
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组织工程
·
止血
·
外科技术
✓ 已验证
DOI
PubMed
高影响因子
BIOCHEMICAL GENETICS
·
2023
·
IF 2.4
Yuan Hang,Yu Peng,Wan Zi-Ang,Chen Bing-Chen,Tu Shi-Liang
We previously reported that long non-coding RNA (lncRNA) RPLP0P2 is involved in the progression of colorectal cancer (CRC); however, its molecular mechanisms in CRC remain unclear. In this study, we observed that RPLP0P2 was upregulated in CRC tissues and cell lines. Cell viability was measured using the MTT and colony formation assays. Migration and invasion capabilities were monitored by wound healing, transwell, and immunofluorescence assays. The results showed that RPLP0P2 downregulation inhibited cell viability, migration, and invasion capabilities of CRC cells, accompanied by decreased PCNA, N-cadherin, and Vimentin, and increased E-cadherin expression. Using the DIANA online database, miR-129-5p was identified as a downstream target of RPLP0P2. In fact, RPLP0P2 colocalized with miR-129-5p, acting as a miR-129-5p sponge. MiR-129-5p-inhibition almost abrogated the anti-tumor effects induced by RPLP0P2 inhibition in CRC cells. Zinc finger and BTB domain-containing 20 (ZBTB20) was identified as a potential downstream target of miR-129-5p in CRC cells. ZBTB20 overexpression prevented miR-129-5p mimic-mediated anti-tumor effects in CRC cells. A tumor xenograft assay was performed to monitor the role of RPLP0P2 in tumor growth. Of note, in tumor-bearing mice, RPLP0P2-silencing inhibited tumor growth, followed by increased miR-129-5p and decreased ZBTB20 expression. Our results suggest that lncRNA RPLP0P2 functions as an oncogene that promotes CRC cell proliferation and invasion via regulating the miR-129-5p/ZBTB20 axis, thus, it may serve as a candidate target for CRC interventional therapies.
研究领域:
肿瘤学
·
分子生物学
·
癌症研究
✓ 已验证
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2013
·Vol. 180
·期 9
·829-835
·
IF 3.434
Zhao Huimin,Gao Sheng,Liu Meng,Chang Yangyang,Fan Xinfei,Quan Xie
We report on a fluorescent assay for oxytetracycline (OTC) using a fluorescein-labeled long-chain aptamer assembled onto reduced graphene oxide (rGO). The π-π stacking interaction between aptamer and rGO causes the fluorescence of the label to be almost completely quenched via energy transfer so that the system has very low background fluorescence. The addition of OTC leads to the formation of G-quadruplex OTC complexes and prevents the adsorption of labeled aptamer on the surface of rGO. As a result, fluorescence is restored, and this effect allows for a quantitative assay of OTC over the 0.1–2 μM concentration range and with a detection limit of 10 nM. This method is simple, rapid, selective and sensitive. It may be applied to other small molecule analytes by applying appropriate aptamers.
A simple and sensitive fluorescent assay for oxytetracycline detection based on the different interaction intensity of fluorescein-labeled long-chain aptamer, G-quadruplex-OTC complex with reduced graphene oxide was designed.
研究领域:
生物化学
·
分析化学
✓ 已验证
DOI
高影响因子
BMC PLANT BIOLOGY
·
2017
·Vol. 17
·期 1
·1-20
·
IF 3.964
Guo Xiaoou,Xu Jingjing,Cui Xiaohui,Chen Hao,Qi Hongyan
Background Oriental melon is one of the most popular crops for its nutritional and flavour quality. Components that determine melon quality, such as sugar, colour, texture, flavour and aroma, among other factors, accumulate in different developmental stages. Thus, correlating the proteomic profiles with the biochemical and physiological changes occurring in the oriental melon is very important for advancing our understanding of oriental melon quality in the ripening processes.Results iTRAQ-based protein profiling was conducted on ‘YuMeiren’ oriental melon fruit at different developmental stages. Physiological quality indices, including firmness, rind colour, soluble solids content (SSC), ethylene production, sugar content and volatile compounds were also characterized during four maturity periods of the melon, including 5, 15, 25 and 35 days after anthesis (DAA). A principal component analysis (PCA) revealed that the aroma volatiles at 5 DAA and 15 DAA were similar and separated from that of 35 DAA. More than 5835 proteins were identified and quantified in the two biological repeats and divided into 4 clusters by hierarchical cluster analysis. A functional analysis was performed using Blast2GO software based on the enrichment of a GO analysis for biological process, molecular function and cellular components. The main KEGG pathways, such as glycolysis, α-linolenic acid and starch and sucrose metabolism, were analyzed.The gene family members corresponding to differentially expressed proteins, including lipoxygenase (CmLOX01-18) and alcohol acetyltransferase (CmAAT1-4) involved in the α-linolenic acid metabolic pathway, were verified with real-time qPCR. The results showed that the expression patterns of 64.7% of the genes were consistent with the expression patterns of the corresponding proteins.Conclusion sThis study combined the variation of the quality index and differentially expressed proteins of oriental melon at different developmental stages that laid the foundation for the subsequent protein and gene function validation.
研究领域:
植物学
·
食品科学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
International Journal of Environmental Science and Technology
·
2020
·Vol. 17
·期 9
·4061-4074
·
IF 2.54
Liu H.,Li D.,Shao L.,Wu D.,Zhang H.,Yuan J.,Xu F.
In this study, a crack-free PDMS–SiO 2 –BiPO 4 (P/Si/Bi) composite was prepared via a solgel-assisted route by dispersing pre-prepared bismuth oxybromide into a solution that was composed of hydroxyl-terminated polydimethylsiloxane (PDMS–OH), tetraethyl orthosilicate and phosphoric acid. Analysis via the FTIR, XRD, XPS and SEM–EDX techniques demonstrated that the nonisolated BiPO 4 particles with a monoclinic crystal phase were uniformly distributed on the surface of the P/Si/Bi composite, which can provide more active sites and a larger surface area for photocatalysis compared with other materials. The photocatalytic activity of the P/Si/Bi composite loaded with various mass ratios of BiPO 4 (9 wt%, 12 wt%, 18 wt% and 27 wt%) was investigated via the degradation of methylene blue (MB, 10 mg/L) under UV light irradiation. It was found that the P/Si/Bi composite loaded with 18 wt% BiPO 4 realized the highest degradation efficiency of MB, and its corresponding apparent rate constant was approximately 2.2 times that of the PDMS–SiO 2 –TiO 2 composite (loaded with 18 wt% TiO 2 ). The effects of inorganic ions on the degradation of MB were also investigated. The static contact angle and photocatalytic activity of the P/Si/Bi composite changed minimally after five cyclic experiments, thereby demonstrating its remarkable durability in sustainable applications. In addition, the photogenerated reactive species that were responsible for the degradation of MB within the P/Si/Bi composite were identified, and a photocatalytic mechanism was proposed.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLUTION CHEMISTRY
·
2017
·Vol. 46
·期 9
·1767-1777
·
IF 1.342
Guo Lijiang,Wang Yaxiao,Tu Lanying,Li Jianqiang
Water activities for the MgCl 2 –RbCl–H 2 O ternary system and its sub-binary MgCl 2 –H 2 O and RbCl–H 2 O systems at 298.15 K have been measured using the isopiestic method. The measured results for the binary systems agree well with literature data. The measured equal water activity lines for the MgCl 2 –RbCl–H 2 O ternary system deviate from Zdanovskii’s rule. The solubilities for the MgCl 2 –RbCl–H 2 O ternary system also have been measured using a isothermal visual first/last crystal method, and the results are consistent with one reported set of solubility data. Pitzer’s model was selected to correlate the measured water activity and solubility data and the parameters reported in the literature are re-examined by comparing the model-calculated equal water activity lines and solubilities with experimental values measured in this work. New and reasonable parameters are obtained by fitting the water activity and solubility data measured in this work and those reported in the literature. The water activities and solubilities were simulated with the new parameters and the results show that the Pitzer model can successfully represent the thermodynamic properties and be used to calculate the solubility isotherms.
研究领域:
化学热力学
·
物理化学
✓ 已验证
DOI
高影响因子
CHEMICAL PAPERS
·
2019
·Vol. 73
·期 7
·1761-1766
·
IF 1.246
Zhang Li-hui,Zhou Yan-biao,Li Wei-li,Zhao Xu-yao,Wang Ya-bo
Lu(OH)CO 3 :Ln 3+ /LuBO 3 :Ln 3+ (Ln = Eu, Tb) nanospheres have been synthesized by the soft chemistry route. This synthesis process does not require the addition of any organic solvents and surfactant. The whole process consists of homogeneous precipitation and hydrothermal process. First, uniform spherical Lu(OH)CO 3 :Ln 3+ (Ln = Eu, Tb) nanoparticles with the sizes of 70 nm were obtained by the classic urea-based homogeneous precipitation. Then, with the above Lu(OH)CO 3 :Ln 3+ (Ln = Eu, Tb) nanosphere as the precursor, the composites of Lu(OH)CO 3 :Ln 3+ /LuBO 3 :Ln 3+ (Ln = Eu, Tb) nanospheres formed by the simple hydrothermal process. The phases, morphologies, as well as the luminescence properties of as-prepared samples were characterized by means of X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and photoluminescence. Under a short wavelength excitation, the down-conversion Eu 3+ and Tb 3+ -doped LuBO 3 samples were investigated and explained.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 17
·10282-10292
·
IF 4.22
Hussain Taimoor,Nie Pengfei,Hu Bin,Shang Xiaohong,Yang Jianmao,Liu Jianyun
Alkaline-earth metal-based MOF has many merits such as light weight, environmental friendliness and low cost, but it has rarely been used in energy storage and capacitive deionization (CDI). This paper presents a facile method for the fast synthesis of small-size magnesium formate MOF (Mg-MOF) under mild conditions by linker-free incubation in the presence of Mg(CH 3 COO) 2 ⋅ 4H 2 O and dimethylformamide. The formic acid was in situ formed as ligand to facilitate the formation of Mg-MOF. The effect of incubation time on the morphology of MOF crystals was investigated. The small and well-defined Mg-MOF particles with the size of ~ 18 nm were formed in 1 h incubation, characterized by scanning electron microscopy and X-ray diffraction. Following carbonization, the Mg-MOF-derived mesoporous carbon was obtained. N 2 -sorption isotherm confirmed the mesoporous structure. Cyclic voltammetry test indicated the good electric double-layer feature of the Mg-MOF-derived carbon electrode, and the impedance results showed the excellent conductivity. As a capacitor electrode material, it delivered the specific capacitances of 102 F/g by GCD (0.2 A/g). The Mg-MOF-derived carbon electrode was applied successfully for capacitive deionization (CDI) with a desalination capacity of 8.0 mg/g in a CDI device. A supper fast desalination rate of 1.1 mg/g/min was achieved due to the abundant mesoporous structure. The work provides a cost effective and environmentally friendly way for the synthesis of MOF-based carbon materials free of transition metal, and the prospects for CDI application have been demonstrated.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）