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Mechanism of Cerium Ions Scavenging Superoxide Radical

第十三届全国量子化学会议

作者： Yanling Luo Ya-Jun Liu Key Laboratory of Theoretical and Computational Photochemistry Ministry of Education College of ChemistryBeijing Normal University

Flavoproteins are kinds of proteins containing flavins as a prosthetic group, which play vital roles in a wide array of biological pr *** can be divided into oxidases and monooxygenases based on their reactivity with oxygen and the corresponding products. The bacterial luciferase is a peculiar flavoprotein monooxygenase involving the amazing bioluminescence phenomenon. The entire bacterial bioluminescence process is initiated by the oxygenation reaction of reduced flavin mononucleotide(FMNH2) in the luciferase. Furthermore,the oxidation of reduced flavin by oxygen is one of the most fascinating reactions in biochemist ry. To interpret the spin-forbidden oxygenation reaction and provide clues for bacterial bioluminescence mechanism, the reaction of lumiflavin with oxygen was studied under vacuum. The results reveal that the oxygenation carries out in accordance with the proton-coupled electron transfer mechanism.

关键词： Oxygenation flavin Bacterial bioluminescence

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Journal of Rare Earths 1998年第1期16卷 47-51页

作者：王金胜郭春绒程玉香 Department of Basic Science Shanxi Agricultural University Taigu 030801 China Jinzhong Health School Taigu 030801 China

The mechanism of cerium ions scavenging superoxide radical(O÷2) has been studied. The results show that (1) Ce^3+ can reduce O÷2 to H_2O_2 while it is oxidized to Ce^4+; (2) Ce^4+ can oxidize O÷2 ... 详细信息

关键词： Rare earths Cerium ion Superoxide radical flavin

Biomimetic asymmetric catalysis

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Science China Chemistry 2023年第6期66卷 1553-1633页

作者： Xiao Xiao Kaini Xu Zhong-Hua Gao Zhou-Hao Zhu Changqing Ye Baoguo Zhao Sanzhong Luo Song Ye Yong-Gui Zhou Senmiao Xu Shou-Fei Zhu Hongli Bao Wei Sun Xiaoming Wang Kuiling Ding State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China The Education Ministry Key Laboratory of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materialsand Shanghai Frontiers Science Center of Biomimetic CatalysisShanghai Normal UniversityShanghai 200234China Center of Basic Molecular Science Department of ChemistryTsinghua UniversityBeijing 100084China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China Key Laboratory of Coal to Ethylene Glycol and Its Related Technology State Key Laboratory of Structural ChemistryCenter for Excellence in Molecular SynthesisFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Enzymes are the core for biological transformations in *** structures and functions have drawn enormous attention from biologists as well as chemists since last *** large demand of bioactive molecules and the pursuit of efficiency and greenness of synthesis have spurred the rapid development of biomimetic chemistry in the past several *** asymmetric catalysis,mimicking the structures and functions of enzymes,has been recognized as one of the most promising synthetic strategies for the synthesis of valuable chiral *** review summarizes the evolution of asymmetric catalysis inspired by aldolases,vitamin B_(1)/B_(6)-dependent enzymes,NAD(P)H,flavin,hydrogenases,heme oxygenases,nonheme oxygenases,and dinuclear/multinuclear metalloenzymes in aspects of biomimetic design,catalyst development and related catalytic *** well-established synthetic approaches originating from biological reactions have demonstrated the unique prowess of biomimetic asymmetric catalysis in bridging the gap between bio-catalysis and chemical synthesis.

关键词： biomimetic catalysis amine catalysis carbene catalysis vitamin Br carbonyl catalysis vitamin Bo NAD(P)H flavin biomimetic oxidation dinuclear/multinuclear metal catalysis asymmetric hydrogenation

LOV to BLUF： Flavoprotein Contributions to the Optogenetic Toolkit

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Molecular Plant 2012年第3期5卷 533-544页

作者： John M. Christie Jayde Gawthorne Gillian Young Niall J. Fraser^c and Andrew J. Roe Institute of Molecular Cell and Systems Biology College of Medical Veterinary and Life Sciences University of Glasgow UK Institute of Infection immunity and Inflammation College of Medical Veterinary and Life Sciences University of Glasgow UK Institute of Cardiovascular and Medical Sciences College of Medical Veterinary and Life Sciences University of Glasgow UK

Optogenetics is an emerging field that combines optical and genetic approaches to non-invasively interfere with cellular events with exquisite spatiotemporal control. Although it arose originally from neuroscience, optogenetics is widely applicable to the study of many different biological systems and the range of applications arising from this tech- nology continues to increase. Moreover, the repertoire of light-sensitive proteins used for devising new optogenetic tools is rapidly expanding. Light, Oxygen, or Voltage sensing （LOV） and Blue-Light-Utilizing flavin adenine dinucleotide （FAD）（BLUF） domains represent new contributors to the optogenetic toolkit. These small （100-140-amino acids） flavoprotein modules are derived from plant and bacterial photoreceptors that respond to UV-A/blue light. In recent years, considerable progress has been made in uncovering the photoactivation mechanisms of both LOV and BLUF domains. This knowledge has been applied in the design of synthetic photoswitches and fluorescent reporters with applications in cell biology and biotechnology. In this review, we summarize the photochemical properties of LOV and BLUF photosensors and highlight some of the recent advances in how these flavoproteins are being employed to artificially regulate and image a variety of biological processes.

关键词： Blue-Light.Utilizing FAD chromophore flavin fluorescence light, oxygen or voltage optogenetics photo- receptor protein engineering

Mechanistic Study of Oxidoreductase AprQ Involved in Biosynthesis of Aminoglycoside Antibiotic Apramycin

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Chinese Journal of Chemistry 2021年第7期39卷 1923-1926页

作者： Jinxiu Wang Suze Ma Wei Ding Tuo Chen Qi Zhang State Key Laboratory of Cryospheric Science Key Laboratory of Extreme Environmental Microbial Resources and EngineeringNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu730000 China Department of Chemistry Fudan UniversityShanghai200433 China University of Chinese Academy of Sciences Beijing100049 China State Key Laboratory of Microbial Metabolism School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai200240 China

Main observation and conclusion The aminoglycoside antibiotic apramycin contains a unique bicyclic octose moiety,and biosynthesis of this moiety involves an oxidoreductase *** other known“Q”series proteins involved in aminoglycosides biosynthesis,AprQ does not work with an aminotransferase partner,and performs a four-electron oxidation that converts a CH2OH moiety to a carboxylate group.

关键词： Biosynthesis flavin Flavoprotein Oxidase Enzyme mechanism

SPECTRA PROPERTIES OF RAT LIVER MITOCHONDRIAL CHOLINE DEHYDROGENASE

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Science China Chemistry 1990年第8期33卷 955-963页

作者：裘之华林其谁 Shanghai Institute of Biochemistry Academia Sinica Shanghai 200031 PRC

Choline dehydrogenase contains the prosthetic group FAD, non-haem iron and acid labile sulfur. However, the absorption spectra of the purified enzyme do not change after adding substrate. The reduced absorption spectra of choline dehydrogenase can only be determined after the addition of dithionite. Those choline dehydrogenases situated in the mitochondrial inner membrane can be reduced by substrate and exist in the reduced state. When cholate was used to solubilize the substrate-reduced choline dehydrogenase, the reduced spectra will gradually disappear. However, if solubilization is carried out under anaerobic conditions, the reduced spectra can be retained, suggesting that the solubilized choline dehydrogenase can use oxygen as an acceptor.

关键词： mitochondria choline dehydrogenase flavin adenine dinucleotide(FAD)

Kinetics and mechanism of electron-induced splitting of a cyclobutane pyrimidine dimer with or without an electron acceptor

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Science China Chemistry 2003年第5期46卷 439-444页

作者：晏利琴宋钦华黑晓明王文锋郭庆祥 Department of Chemistry University of Science and Technology of China Hefei 230026 China Laboratory of Radiation Chemistry Shanghai Institute of Nuclear Research Chinese Academy of Sciences Shanghai 201800 China

Utilizing a pulse radiolysis equipment with time-resolved optical detector, kinetic processes of electron-induced splitting of cis-syn 1,3-dimethyluracil cyclobutane dimer (DMUD) in aqueous solution were investigated in the presence or absence of riboflavin (RF) or flavin adenine dinucleotide (FAD). It has been observed that the cyclobutane pyrimidine dimer reacting with hydrated electron splits spontaneously to give a monomer and a monomer radical anion, and the anion transfers one electron to RF or FAD. From the buildup kinetics of radical species, the rate constants of electron transfer from the monomer radical anion to RF and FAD have been determined. On the basis of comparison of the interactions between DMUD and hydrated electron in the presence and absence of RF or FAD, a chain reaction process in the absence of RF or FAD has been demonstrated.

关键词： cyclobutane pyrimidine dimer, pulse radiolysis, riboflavin, flavin adenine dinucleotide, electron transfer, DNA photoreactivation.

Recent Advances in Photoenzymatic Catalysis

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International Journal of Organic Chemistry 2024年第2期14卷 69-91页

作者： Caiyi Xiang School of Chemical and Biomolecular Engineering Georgia Institute of Technology Atlanta GA USA

Photoenzymatic catalysis has become an emerging field in organic synthetic chemistry that provides eco-friendly alternatives to traditional methods. This comprehensive review examines the developing field of photoenzymatic catalysis, categorized by reaction types and focusing on its application in organic synthesis. This article highlights recent advances in the use of photoenzymatic reactions in carbon-carbon cross-coupling, ketone and alkene reduction, hydroamination, and hydrosulfonylation, mostly by flavin-dependent “ene”-reductases and nitroreductases. In each case, we exemplified the substrate scope that produces products with high yield and enantioselectivity. Additionally, the emerging trends in developing new enzymatic variants and novel reaction pathways that broaden the scope and enhance yield of these reactions were discussed.

关键词： Photoenzymatic Biocatalysis Biocatalysts ERED “Ene”-Reductases Nitroreductases flavin

Rapid and Non-Invasive Screening System for Early Detection of Diabetic Retinopathy via Auto Fluorescence of <i>Falvin</i>Proteins

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Journal of Biomedical Science and Engineering 2018年第8期11卷 215-224页

作者： Bin Gao Yang Li Qifeng Jiang Department of Medical Information Chongqing Medical University Chongqing China Department of Biochemistry and Molecular Biology Chongqing Medical University Chongqing China

Diabetic retinopathy is one of the most serious complications of diabetes, which is also one of the most important causes of blindness around the world. Autofluorescence of flavin protein in retinal pigment epithelial cells is considered as a marker of early tissue damage. This study was designed to image spontaneous fluorescence of falvin proteins in fundus macular center area. The average intensity of the fluorescence signal and the characteristics of the histogram distribution were obtained and the significant differences in the fluorescence signals between the diabetic and the normal people were also compared with statistical methods, and then a rapid and non-invasive screening method and equipment for early detection of diabetic retinopathy were developed.

关键词： Diabetic Retinopathy Fundus Macular flavin Protein Autofluorescence