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A Novel Fluorescent Reagent for Analysis of Hydrogen Peroxide

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Chinese Journal of Chemistry 2003年第2期21卷 189-191页

作者：董素英苏美红聂丽华马会民 Laboratory of chemical biology Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Dichloro 1,3,5 triazinoxy)quinoline (DTQ) was evaluated as a new fluorescent reagent for determining hydrogen peroxide. It was found that the fluorescence intensity of DTQ in alkaline medium could be dramatically enhanced upon addition of H 2O 2. Based on this effect, a simple and selective method for the spectrofluorimetric determination of hydrogen peroxide was established. The relative standard deviation of the method was found to be 1 1% for 9 replicate determinations of a 4 6×10 -6 mol/L hydrogen peroxide solution. The linear range was 2 3×10 -7 -2 3×10 -5 mol/L with a detection limit of 2 2×10 -8 mol/L ( S/N =3). The method was attempted to determine hydrogen peroxide in synthetic human serum samples with satisfactory results.

关键词： dichloro 1,3,5 triazinoxy)quinoline hydrogen peroxide serum fluorescence

Synthesis and Crystal Structure of 2,3,4,6-Tetra-O-acetyl-1-{2-[(4-nitrophenoxy)methyl]-1,3,4-thiadiazole-5-thione-4-yl}-1-deoxy-β-D-glucopyranose

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Chinese Journal of Structural Chemistry 2010年第5期29卷 747-751页

作者：王致峰赵桂龙田来进 School of Chemistry and chemical Engineering Qufu Normal University Tianjin Key Laboratory of molecular design and Drug Discovery Tianjin Institute of Pharmaceutical Research

The title compound has been synthesized and its crystal structure was determined by single-crystal X-ray *** crystal is of orthorhombic system （C23H25N3O12S2,Mr=599.58）,space group P212121 with a=6.2102（12）,b=17.803（4）,c=24.223（5）,V=2678.0（9）3,Z=4,Dc=1.487 g/cm3,F（000）=1248,μ=0.268 mm-1,the final R=0.0483 and wR=0.1108 for 4174 observed reflections （I 〉 2σ（I））.The C=S bond,which parallels to the anomeric C-H,adopts α orientation relative to the anomeric position of glucopyranoside.

关键词： synthesis crystal structure thiadiazole glucose SGLT2 inhibitor

Using selenium-conjugated polyethylene glycol to enhance the stability of gold nanoparticles in biologically relevant samples

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Science China Chemistry 2019年第2期62卷 280-286页

作者： Yang Xue Bo Dong Xuehui Liu Fengchao Wang Jie Yang Dingbin Liu State Key Laboratory of Medicinal chemical biology Research Center for Analytical Sciences and Tianjin Key Laboratory of Molecular Recognition and Biosensing College of Chemistry Nankai University Collaborative Innovation Center of chemical Science and Engineering (Tianjin)

Using stabilizing agents to maintain the physicochemical properties of colloids in complex environments is crucial for their realworld applications. In this article, we describe how selenium-(Se-) terminated polyethylene glycol(PEG) can serve as a highaffinity stabilizing agent for gold nanoparticles(AuNPs). Compared to Au NPs modified with standard thiolated PEG(S-PEG),Se-PEG-coated Au NPs are much more stable under extreme conditions such as high/low pH, high salt content, and high temperatures. We demonstrate that the Se anchor can prevent the dissociation of PEG ligands from Au NP surfaces in living cells,where a higher concentration of biothiols is usually present. These results indicate that Se-PEG is an excellent stabilizing agent that may facilitate further studies on metal NPs for various complex and physiological systems.

关键词： selenium polyethylene glycol gold nanoparticles biological stability

Qingfei Xiaoyan Wan,a traditional Chinese medicine formula, ameliorates Pseudomonas aeruginosa–induced acute lung inflammation by regulation of PI3K/AKT and Ras/MAPK pathways

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Acta Pharmaceutica Sinica B 2016年第3期6卷 212-221页

作者： Yuanyuan Hou Yan Nie Binfeng Cheng Jin Tao Xiaoyao Ma Min Jiang Jie Gao Gang Bai State Key Laboratory of Medicinal chemical biology and College of Pharmacy Nankai University Tianjin Key Laboratory of molecular Drug Research Nankai University

Gram-negative pathogen–induced nosocomial infections and resistance are a most serious menace to global public health. Qingfei Xiaoyan Wan(QF), a traditional Chinese medicine(TCM)formula, has been used clinically in China for the treatment of upper respiratory tract infections, acute or chronic bronchitis and pulmonary infection. In this study, the effects of QF on Pseudomonas aeruginosa–induced acute pneumonia in mice were evaluated. The mechanisms by which four typical antiinflammatory ingredients from QF, arctigenin(ATG), cholic acid(CLA), chlorogenic acid(CGA) and sinapic acid(SPA), regulate anti-inflammatory signaling pathways and related targets were investigated using molecular biology and molecular docking techniques. The results showed that pretreatment with QF significantly inhibits the release of cytokines(TNF-α and IL-6) and chemokines(IL-8 and RANTES),reduces leukocytes recruitment into inflamed tissues and ameliorates pulmonary edema and necrosis. In addition, ATG was identified as the primary anti-inflammatory agent with action on the PI3K/AKT and Ras/MAPK pathways. CLA and CGA enhanced the actions of ATG and exhibited synergistic NF-κB inactivation effects possibly via the Ras/MAPK signaling pathway. Moreover, CLA is speculated to target FGFR and MEK firstly. Overall, QF regulated the PI3K/AKT and Ras/MAPK pathways to inhibit pathogenic bacterial infections effectively.

关键词： Anti-inflammatory Network pharmacology Pathogenic bacterial infection PI3K/AKT pathway Ras/MAPK pathway Lung Mouse

Techniques for detecting protein-protein interactions in living cells:principles, limitations, and recent progress

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Science China(Life Sciences) 2019年第5期62卷 619-632页

作者： Yaning Cui Xi Zhang Meng Yu Yingfang Zhu Jingjing Xing Jinxing Lin Beijing Advanced Innovation Center for Tree Breeding by molecular design Beijing Forestry University College of Biological Sciences & Biotechnology Beijing Forestry University Institute of Plant Stress biology State Key Laboratory of Cotton Biology Department of Biology Henan University

Detecting protein-protein interactions(PPIs) provides fundamental information for understanding biochemical processes such as the transduction of signals from one cellular location to another; however, traditional biochemical techniques cannot provide sufficient spatio-temporal information to elucidate these molecular interactions in living cells. Over the past decade, several new techniques have enabled the identification and characterization of PPIs. In this review, we summarize three main techniques for detecting PPIs in vivo, focusing on their basic principles and applications in biological studies. We place a special emphasis on their advantages and limitations, and, in particular, we introduced some uncommon new techniques, such as single-molecule FRET(smFRET), FRET-fluorescence lifetime imaging microscopy(FRET-FLIM), cytoskeleton-based assay for protein-protein interaction(CAPPI) and single-molecule protein proximity index(smPPI), highlighting recent improvements to the established techniques. We hope that this review will provide a valuable reference to enable researchers to select the most appropriate technique for detecting PPIs.

关键词： protein-protein interactions in vivo techniques RET PCA co-localization

Synthesis and Photocleaving DNA Activity of 4′-Chlorobenzene-sulfonyl Chloride-pyrrolecarboxamide Hybrid Compound

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Chinese Journal of Chemistry 2003年第9期21卷 1238-1240页

作者：汤菲力袁谷 Laboratory of Bioorganic Chemistry and molecular Engineering Ministry of Education Department of Chemical Biology College of Chemistry Peking University Beijing 100871 China

A 4′-chlorobenzenesulfonyl chloride-pyrrolecarboxamide hybrid compound was synthesized and its DNA cleaving activity was investigated using a pBluescript SK DNA under UV irradiation. This compound showed potent DNA c... 详细信息

关键词： photonuclease DNA cleaving polyamide

Fluorescence quenching of TMR by guanosine in oligonucleotides

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Science China Chemistry 2009年第10期52卷 1653-1659页

作者： QU Peng CHEN XuDong ZHOU XiaoXue LI Xun ZHAO XinSheng Beijing National Laboratory for molecular Sciences State Key Laboratory for Structural Chemistry of Unstable and Stable Speciesand Department of Chemical BiologyCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Nucleotide-specific fluorescence quenching in fluorescently labeled DNA has many applications in biotechnology. We have studied the inter-and intra-molecular quenching of tetramethylrhodamine (TMR) by nucleotides to better understand their quenching mechanism and influencing factors. In agreement with previous work, dGMP can effectively quench TMR, while the quenching of TMR by other nucleotides is negligible. The Stern-Volmer plot between TMR and dGMP delivers a bimolecular quenching constant of Ks=52.3 M-1. The fluorescence of TMR in labeled oligonucleotides decreases efficiently through photoinduced electron transfer by guanosine. The quenching rate constant between TMR and guanosine was measured using fluorescence correlation spectroscopy (FCS). In addition, our data show that the steric hindrance by bases around guanosine has significant effect on the G-quenching. The availability of these data should be useful in designing fluorescent oligonucleotides and understanding the G-quenching process.

关键词： TMR guanosine fluorescence oligonucleotides G-quenching PET FCS

Distinguishable multi-substance detection based on three-channel NIR fluorescent probe in physiology and pathology of living cells and zebrafish

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Chinese chemical Letters 2021年第12期32卷 3870-3875页

作者： Sha Li Fangjun Huo Yongkang Yue Kaiqing Ma Ying Wen Caixia Yin Institute of molecular Science Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of EducationShanxi UniversityTaiyuan 030006China Research Institute of Applied Chemistry Shanxi UniversityTaiyuan 030006China

Mitochondria is the main organelle for the production of reactive sulfur species(RSS), such as homocysteine(Hcy), cysteine(Cys), glutathione(GSH) and sulfur dioxide(SO_(2)). These compounds participate in a large number of physiological processes and play an extremely important role in maintaining the balance of life systems. Abnormal concentration and metabolism are closely related to many diseases. Due to their similarities in chemical properties, it is challenging to develop a single fluorescent probe to distinguish them simultaneously. Here, we synthesized the probe PI-CO–NBD with three fluorophores, NBD-Cl and benzopyranate as the reaction sites of GSH/Cys/Hcy and SO_(2), respectively. Three biothiols all could cleavage ether bond to release benzopyrylium and coumarin moiety, which emitted red and blue fluorescence,but Cys/Hcy also could do intramolecular rearrangement after nucleophilic substitution, resulting in yellow fluorescence. Thus the probe can distinguish Cys/Hcy and GSH. Subsequently, only SO_(2)could quench red fluorescence by adding C=C of benzopyrylium. The probe also could localize well in mitochondria by oxonium ion for all kinds of cells. The probe not only could detect above sulfur-containing active substances of intracellular and extracellular but also monitor the level of them under oxidative stress and apoptosis process in living cells and zebrafish.

关键词： Mitochondrial-targeted Discrimination detection Distinguishable Multi-substance Three channels

Marking RNA:m^6A writers,readers,and functions in Arabidopsis

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Journal of molecular Cell biology 2019年第10期11卷 899-910页

作者： Marlene Reichel Tino Koster Dorothee Staiger RNA biology and molecular Physiology Faculty of BiologyBielefeld University33615 BielefeldGermany

N^6-methyladenosine(m^6A)emerges as an important modification in eukaryotic mRNAs.m^6A has first been reported in 1974,and its functional significance in mammalian gene regulation and importance for proper development have been well *** arsenal of writer,eraser,and reader proteins accomplish deposition,removal,and interpretation of the m^6A mark,resulting in dynamic *** led to the concept of an epitranscriptome,the compendium of RNA species with chemical modification ofthe nucleobases in the cell,in analogy to the *** m^6A has long been known to also exist in plant mRNAs,proteins involved in m^6A metabolism have only recently been detected by mutant analysis,homology search,and mRNA interactome capture in the reference plant Arabidopsis *** ofthe m^6A modification causes severe developmental abnormalities of leaves and roots and altered timing of reproductive ***,m^6A modification affects viral ***,we discuss recent progress in identifying m^6A sites transcriptome-wide,in identifying the molecular players involved in writing,removing,and reading the mark,and in assigning functions to this RNA modification in *** highlight similarities and differences to m^6A modification in mammals and provide an outlook on important questions that remain to be addressed.

关键词： Arabidopsis m^6A mRNA interactome posttranscriptional RNA-binding protein