检索结果-南通市图书馆

chinese chemical letters 2024年第4期35卷 426-430页

作者： Tiantian li Ruochen Jin Bin wu Dongming lan Yunjian Ma Yonghua Wang School of Food Science and Engineering South China University of TechnologyGuangzhou 510640China School of Bioscience and Bioengineering South China University of TechnologyGuangzhou 510006China Guangdong Youmei Institute of Intelligent Bio-manufacturing co. Ltd.Foshan 528200China

Unspecific peroxygenases(UPOs, Ec 1.***.2.1) is a kind of thioheme enzyme capable of catalyzing various oxidations of inert c–H bonds using H_(2)O_(2) as an oxygen donor without cofactors. However, the enhancement of the H_(2)O_(2) tolerance of UPOs is always challenging. In this study, the A161c mutant of r Dca UPO,which originates from Daldinia caldariorum, was found to be highly H_(2)O_(2)-resistant. compared with the wild type, the mutant r Dca UPO-A161c showed a 10-h prolonged half-life and a 64% improved enzyme activity when incubated in 10 mmol/l H_(2)O_(2). The crystal structure analysis at 1.47 A showed that r Dca UPOA161c exhibited 10 α-helixes(cyan) and a series of ordered rings, forming a single asymmetric spherical structure. The two conserved domains near heme formed an active site with the catalytic PcP and EHD regions(Glu86, His87, Asp88 residues). The H_(2)O_(2) tolerance of r Dca UPO-A161c was preliminarily explored by comparing its structure with the wild type. Notably, r Dca UPO-A161c showed significantly higher catalytic efficiency than the wild type for the production of hydroxyl fatty acids. This study is anticipated to provide an insight into the structure-function relationship and expand potential applications of UPOs.

关键词： Unspecific peroxygenase Molecular modification Hydrogen peroxide stability crystal structure Hydroxyl fatty acids

S-methyl-l-cysteine Protects against Antimycin A-induced Mitochondrial Dysfunction in Neural cells via Mimicking Endogenous Methionine-centered Redox cycle

在线全文

学校读者我要写书评

暂无评论

current Medical Science 2020年第3期40卷 422-433页

作者： lan NI Xin-lei GUAN Fu-feng cHEN Peng-fei wu Department of Pharmacology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Pharmacy Wuhan Puai HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430033China Tongji-Rongcheng center for Biomedicine Wuhan 430030China Key laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province Wuhan 430030China

Mitochondrial superoxide overproduction is believed to be responsible for the neurotoxicity associated with ***-targeted antioxidants,such as MitoQ,have emerged as potentially effective antioxidant *** sulfoxide reductase A(MsrA)is a key mitochondrial-localized endogenous antioxidative enzyme and it can scavenge oxidizing species by catalyzing the methionine(Met)-centered redox cycle(McRc).In this study,we observed that the natural l-Met acted as a good scavenger for antimycin A-induced mitochondrial superoxide overproduction in Pc12 *** antioxidation was largely dependent on the Met oxidase activity of MsrA.S-methyl-l-cysteine(SMlc),a natural analogue of Met that is abundantly found in garlic and cabbage,could activate the Met oxidase activity of MsrA to scavenge free ***,SMlc protected against antimycin A-induced mitochondrial membrane depolarization and alleviated 1-methyl-4-phenylpyridinium(MPP+)-induced ***,our data highlighted the possibility for SMlc supplement in the detoxication of mitochondrial damage by activating the Met oxidase activity of MsrA.

关键词： methionine sulfoxide reductase A Met oxidase S-methyl-l-cysteine neurotoxin 1-methyl-4-phenylpyridinium

A benzo[ghi]-perylene triimide based double-cable conjugated polymer for single-component organic solar cells

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

chinese chemical letters 2022年第1期33卷 466-469页

作者： Dan Wang Zhaofan Yang Feng liu chengyi Xiao Yonggang wu Weiwei li college of chemistry and Environmental Science Hebei UniversityBaoding 071002China Beijing Advanced Innovation center for Soft Matter Science and Engineering&State Key laboratory of Organic-Inorganic composites Beijing University of Chemical TechnologyBeijing 100029China college of Basic Medicine Hebei UniversityBaoding 071002China

Single-component organic solar cells(ScOScs)with high stability and simplified fabrication process are supposed to accelerate the commercialization of organic ***,the types of photo-active materials and photovoltaic performance of ScOScs are still far lagging behind the bulk-heterojunction type organic solar cells(BHJ OScs).It is still an arduous task to introduce new photo-active materials into ScOScs,aiming to improve the efficiencies of *** feasible way is to construct double-cable polymers with new structures and tune conformation,morphology and mobility for the improvement in power conversion efficiencies(PcEs).Hence,in this work,we constructed a new double-cable polymer PBTT-BPTI by introducing fused core 5,7-dibromo-2,3-bis(2-ethylhexyl)benzo[1,2-b:4,5-c’]dithiophene-4,8-dione(TTDO)into the main backbone and benzo[ghi]-perylene triimide(BPTI)unit into the side *** of the two units show strong electron-withdrawing property,which are expected to broaden absorption spectra and enhance intermolecular *** double-cable polymer exhibited a broad absorption in the range of 300-700 nm with an optical band gap(E_(g))of 1.79 *** PcE of PBTT-BPTI-based ScOScs was 2.15%,which may be limited by the unconstructed efficient electron transporting channels.

关键词： Double-cable polymer Single-component organic solar cells BPTI Electron withdrawing Electron transporting channels

Total Water Management Strategy In Hong Kong

在线全文

学校读者我要写书评

暂无评论

Total Water Management Strategy In Hong Kong

The RNF20/40 complex regulates p53-dependent gene transcription and mRNA splicing

第四届粤港澳可持续发展研讨会

作者： Bobby M T NG c l Wong Alan H l MAN Gigi l c lAM Water Supplies Department Hong Kong SAR Black & Veatch Hong Kong SAR

Today,sustainability of life supporting resources including clean fresh water is a global challenge for *** availability of these resources is declining,the demand for their consumption continues to *** is evident in the Pearl River Delta(PRD)region where unprecedented growth in economy has sparked keen demand for fresh water resources within the *** change adds further uncertainty to the *** Hong Kong will have adequate water supply to cope with the projected demand in the coming two decades with the importation of Dongjiang water,to better prepare for uncertainties such as climate change as well as to help enhance Hong Kong’s role as a good partner of other municipalities in the PRD region in promoting sustainable use of water,the Hong Kong Special Administrative Region(HKSAR)Government commissioned Black & Veatch(B&V)to undertake a compre- hensive study on the Total Water Management(TWM)in Hong *** into account local conditions and overseas experiences,the TWM study has considered all major options of water demand management measures as well as water supply management *** water de- mand/supply management option has been evaluated in terms of quantity of water saved or sup- plied,cost effectiveness,environmental impact and public *** on the findings of the study,a TWM strategy is formulated for the period up to year 2030.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Molecular cell Biology 2020年第2期12卷 113-124页

作者： chen wu Yaqi cui Xiuhua liu Feng Zhang lin-Yu lu Xiaochun Yu college of life Sciences Hebei UniversityBaoding 071000China Department of cancer Genetics and Epigenetics Beckman Research InstituteCity of HopeDuarteCA 91010USA college of life and Environment Sciences Shanghai Normal UniversityShanghaiChina Key laboratory of Reproductive Genetics Ministry of Education and Women's Reproductive Health Laboratory of Zhejiang ProvinceWomen's HospitalSchool of MedicineZhejiang UniversityHangzhouChina Institute of Translational Medicine Zhejiang UniversityHangzhouChina

p53 is a key transcription factor to regulate gene ***,the molecular mechanism of chromatin-associated p53 on gene transcription remains ***,using unbiased protein affinity purification,we found that the RNF20/40 complex associated with p53 on the *** analyses indicated that p53 mediated the recruitment of the RNF20/40 complex to p53 target gene loci including p21 and PUMA loci and regulated the transcription of p21 and PUMA via the RNF20/40 complex-dependent histone H2B ubiquitination(ubH2B).lacking the RNF20/40 complex suppressed not only ubH2B but also the generation of the mature mRNA of p21 and ***,ubH2B was recognized by the ubiquitin-binding motif of pre-mRNA processing splicing factor 8(PRPF8),a subunit in the spliceosome,and PRPF8 was required for the maturation of the mRNA of p21 and *** study unveils a novel p53-dependent pathway that regulates mRNA splicing for tumor suppression.

关键词： RNF20 RNF40 gene transcription p53 p21 PUMA

Degradation and resynthesis of chlorophyll during increased oxidative stress and prolonged darkness differ between annual and perennial flax(linum l.)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Oil crop Science 2024年第2期9卷 121-130页

作者： Kenyon J. Nisbett Abida Alokozai Su Hyun Elizabeth Ko G. Adam Mott Jason c.l. Browna Department of Biological Sciences University of Toronto ScarboroughTorontoONCanada Department of cell&Systems Biology University of TorontoTorontoONCanada centre for the Analysis of Genome Evolution&Function University of TorontoTorontoONCanada

Among plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 *** proposed by the Disposable Soma Theory,this lifespan variation among plants likely reflects differential investment of limited energy and nutrient resources,with perennials investing more energy and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple *** differential investment may be particularly important during periods of exogenous stress,which are known to accelerate biomolecular *** present study evaluated this hypothesis using annual and perennial flax(linum l.)subjected to two exogenous stressors—increased oxidative stress(i.e.,foliar H2O2spraying)and complete prolonged *** chlorophyll has been shown to exhibit degradation in response to changes in environmental conditions,we utilized changes in chlorophyll levels during and after periods of exogenous stress to evaluate our *** predicted that i)perennials would exhibit a slower rate of chlorophyll degradation during exposure to exogenous stressors compared to annuals,and ii)perennials would exhibit a faster rate of chlorophyll resynthesis following such exposure compared to *** levels before,during,and after exposure to both exogenous stressors were measured in two separate trails,once using image colour analysis and once using *** chlorophyll degradation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following such exposure were significantly higher in perennials,as *** plants were subjected to complete prolonged darkness,chlorophyll degradation rates were significantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,ch

关键词： Ageing life history Maximum lifespan Oxidative stress Somatic maintenance

Dynamic Spectrum control-Assisted Secure and Efficient Transmission Scheme in Heterogeneous cellular Networks

在线全文

学校读者我要写书评

暂无评论

Engineering 2022年第10期17卷 220-231页

作者： chenxi li lei Guan Huaqing wu Nan cheng Zan li Xuemin(Sherman)Shen State Key laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China Department of Electrical and computer Engineering University of WaterlooWaterlooON N2L 3G1Canada collaborative Innovation center of Information Sensing and Understanding Xi’an 710071China

Heterogeneous cellular networks(HcNs)are envisioned as a promising architecture to provide seamless wireless coverage and increase network ***,the densified multi-tier network architecture introduces excessive intra-and cross-tier interference and makes HcNs vulnerable to eavesdropping *** this article,a dynamic spectrum control(DSc)-assisted transmission scheme is proposed for HcNs to strengthen network security and increase the network ***,the proposed DSc-assisted transmission scheme leverages the idea of block cryptography to generate sequence families,which represent the transmission decisions,by performing iterative and orthogonal sequence *** on the sequence families,multiple users can dynamically occupy different frequency slots for data transmission *** addition,the collision probability of the data transmission is analyzed,which results in closed-form expressions of the reliable transmission probability and the secrecy ***,the upper and lower bounds of network capacity are further derived with given requirements on the reliable and secure transmission *** results demonstrate that the proposed DSc-assisted scheme can outperform the benchmark scheme in terms of security ***,the impacts of key factors in the proposed DSc-assisted scheme on the network capacity and security are evaluated and discussed.

关键词： Heterogeneous cellular networks Dynamic spectrum control Transmission security Efficient data transmission

Effective anti-inflammatory phenolic compounds from dandelion:identification and mechanistic insights using UHPlc-ESI-MS/MS,fluorescence quenching and anisotropy,molecular docking and dynamics simulation

在线全文

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2023年第6期12卷 2184-2194页

作者： Hui Zou Tingting Ben Ping wu Geoffrey I.N.Waterhouse Yilun chen college of Food Science and Engineering Shandong Agricultural UniversityKey Laboratory of Food Processing Technology and Quality Control in Shandong ProvinceTai’an 271018China School of chemical Sciences University of AucklandAuckland 1142New Zealand

This novel study identifi es the effective anti-inflammatory phenolic compounds in dandelion and provides mechanistic insights into their interactions with receptor proteins(toll-like receptor 4,TlR4;co-receptor myeloid differentiation protein-2,MD-2)using UHPlc-ESI-MS/MS,lipopolysaccharide(lPS)-stimulated THP-1 cell line,fluorescence quenching and anisotropy,molecular docking(single ligand and multi-ligand docking)and molecular dynamics simulation.A 50%aqueous methanol extract had a greater anti-inflammatory effect and higher chicoric acid content,compared with the 100%water and 100%methanol *** acid,chlorogenic acid,methylophiopogonone A,caffeic acid,gallic acid monohydrate and 4’-O-demethylbroussonin A had relatively high binding energies and contents in all *** acid competed with chlorogenic acid,4’-O-demethylbroussonin A and quercetin for *** dandelion’s phenolics,chicoric acid most effectively hindered TlR4-MD-2 complex formation,with a quenching constant of 0.62×10^(6) l/mol for MD-2 or TlR4 at 320 K,and binding energies of-6.87 and-5.97 kcal/mol,respectively,for MD-2 and TlR4.

关键词： Dandelion extracts Phenolic compounds binding affinity TlR4-MD-2 antagonist Anti-inflammatory agent

Regulation of the urea cycle by cPS1 O-GlcNAcylation in response to dietary restriction and aging

在线全文

学校读者我要写书评

暂无评论

Journal of Molecular cell Biology 2022年第3期14卷 36-47页

作者： Jing wu Jiayu liu Kalina lapenta Reina Desrouleaux Min-Dian li Xiaoyong Yang Department of comparative Medicine Department of Cellular and Molecular Physiologyand Yale Center for Molecular and Systems MetabolismYale University School of MedicineNew HavenCT 06520USA School of life Science and Technology Xi’an Jiaotong UniversityXi’an 710049China

O-linked N-acetyl-glucosamine glycosylation(O-GlcNAcylation)of intracellular proteins is a dynamic process broadly implicated in age-related disease,yet it remains uncharacterized whether and how O-GlcNAcylation contributes to the natural aging process.O-GlcNAc transferase(OGT)and the opposing enzyme O-GlcNAcase(OGA)control this nutrient-sensing protein modification in ***,we show that global O-GlcNAc levels are increased in multiple tissues of aged *** aged liver,carbamoyl phosphate synthetase 1(cPS1)is among the most heavilyO-GlcNAcylated ***1O-GlcNAcylation is reversed by calorie restriction and is sensitive to genetic and pharmacological manipulations of theO-GlcNAc *** glucose stimulates cPS1O-GlcNAcylation and inhibits cPS1 ***-specific deletion of OGT potentiates cPS1 activity and renders cPS1 irresponsive to further stimulation by a prolonged *** results identify cPS1 O-GlcNAcylation as a key nutrient-sensing regulatory step in the urea cycle during aging and dietary restriction,implying a role for mitochondrial O-GlcNAcylation in nutritional regulation of longevity.

关键词： ageing O-GlcNAcylation urea cycle carbamoyl phosphate synthetase 1 calorie restriction posttranslational modification dietary restriction

Annealing and strain rate effects on the mechanical behavior of ultrafine-grained iron produced by SPD

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Theoretical & Applied Mechanics letters 2011年第2期1卷 12-14页

作者： Fuping Yuan,~(a) Ping Jiang,~(b) and Xiaolei wu~(c) State Key laboratory of Nonlinear Mechanics,Institute of Mechanics chinese Academy of Science, Beijing 100190,china State Key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Science Beijing 100190 China

Thermal stability and strain rate sensitivity of ultrafine-grained(UFG)Fe produced by severe plastic deformation(SPD)were *** UFG Fe was processed by equal-channel angular pressing(EcAP)via route *** 6 passes,the grain size of UFG Fe reaches 600 nm, as confirmed by means of electron back scatter diffraction(EBSD).Examination of micro-hardness and grain size of UFG Fe as a function of post-EcAP annealing temperature shows a transition from recovery to *** critical transition temperature is approximately 500℃,and the material has a bimodal structure after annealing at this *** behaviors of EcAP Fe and EcAP + annealing Fe were studied under both quasi-static and dynamic compressive *** UFG iron shows increased strength and reduced strain rate sensitivity compared with its coarse-grained *** appropriate post-EcAP annealing can increase strain hardening ability and cancel out thermal softening effect with only a small loss of strength under dynamic loading.

关键词： UFG/Nc Fe EcAP EBSD thermal stability strain rate sensitivity