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Steroidal scaffold decorations in Solanum alkaloid biosynthesis

Molecular Plant 2024年第8期17卷 1236-1254页

作者： Rosalind Lucier Mohamed O.Kamileen Yoko nakamura Sofia Serediuk Ranjit Barbole jens Wurlitzer Maritta Kunert Sarah Heinicke Sarah E.O'Connor Prashant D.Sonawane Department of natural Product Biosynthesis Max Planck Institute for Chemical Ecology07745 JenaGermany Research Group Biosynthesis and nMR Max Planck Institute for Chemical Ecology07745 JenaGermany Biochemical Sciences Division CSIR-National Chemical LaboratoryPune 411008MaharashtraIndia

Steroidal glycoalkaloids(SGAs)are specialized metabolites produced by hundreds of Solanum species,including important vegetable crops such as tomato,potato,and *** it has been known that SGAs play important roles in defense in plants and“anti-nutritional"effects(e.g.,toxicity and bitterness)to humans,many of these molecules have documented anti-cancer,anti-microbial,antiinflammatory,anti-viral,and anti-pyretic *** these,α-solasonine andα-solamargine isolated from black nightshade(Solanum nigrum)are reported to have potent anti-tumor,anti-proliferative,and anti-inflammatory ***,α-solasonine andα-solamargine,along with the core steroidal aglycone solasodine,are the most widespread SGAs produced among the Solanum ***,it is still unknown how plants synthesize these bioactive steroidal *** comparative metabolomictranscriptome-guided approach,biosynthetic logic,combinatorial expression in nicotiana benthamiana,and functional recombinant enzyme assays,here we report the discovery of 12 enzymes from *** that converts the starting cholesterol precursorto solasodine aglycone,and the downstreamα-solasonine,α-solamargine,and malonyl-solamargine SGA *** further identified six enzymes from cultivated eggplant that catalyze the production ofα-solasonine,α-solamargine,and malonyl-solamargine SGAs from solasodine aglycone via glycosylation and atypical malonylation *** work provides the gene tool box and platform for engineering the production of high-value,steroidal bioactive molecules inheterologoushosts usingsyntheticbiology.

关键词： steroidal glycoalkaloids Solanum biosynthetic pathway α-solamargine malonyl-solamargine specialized metabolites

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Metabolic collaboration between cells in the tumor microenvironment has a negligible effect on tumor growth

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The Innovation 2024年第2期5卷 107-114页

作者： Johan Gustafsson Fariba Roshanzamir Anders Hagnestål Sagar M.Patel Oseeyi I.Daudu Donald F.Becker Jonathan L.Robinson jens.nielsen Department of Life Sciences Chalmers University of TechnologySE-41296 GothenburgSweden Hagnesia AB SE-43854 HindåsSweden Department of Biochemistry and Redox Biology Center University of Nebraska-LincolnLincolnNE 68588USA BioInnovation Institute DK2200 CopenhagenDenmark

The tumor microenvironment is composed of a complex mixture of different cell types interacting under conditions of nutrient deprivation,but the metabolism therein is not fully understood due to difficulties in measuring metabolic fluxes and exchange of metabolites between different cell types in ***-scale metabolic modeling enables estimation of such exchange fluxes as well as an opportunity to gain insight into the metabolic behavior of individual cell ***,we estimated the availability of nutrients and oxygen within the tumor microenvironment using concentration measurements from blood together with a metabolite diffusion *** addition,we developed an approach to efficiently apply enzyme usage constraints in a comprehensive metabolic model of human *** combined modeling reproduced severe hypoxic conditions and the Warburg effect,and we found that limitations in enzymatic capacity contribute to cancer cells’preferential use of glutamine as a substrate to the citric acid ***,we investigated the common hypothesis that some stromal cells are exploited by cancer cells to produce metabolites useful for the cancer *** identified over 200 potential metabolites that could support collaboration between cancer cells and cancer-associated fibroblasts,but when limiting to metabolites previously identified to participate in such collaboration,no growth advantage was *** work highlights the importance of enzymatic capacity limitations for cell behaviors and exemplifies the utility of enzyme-constrained models for accurate prediction of metabolism in cells and tumor microenvironments.

关键词： metabolism effect limitations

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Urban-induced changes in tree leaf litter accelerate decomposition

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Ecological Processes 2015年第1期4卷 1-16页

作者： jens Dorendorf Anja Wilken annette Eschenbach Kai jens.n Applied Plant Ecology Biocenter Klein FlottbekUniversität HamburgOhnhorstraße 1822609 HamburgGermany Institute for Soil Science CENUniversität HamburgAllende-Platz 220146 HamburgGermany.

Introduction:The role of urban areas in the global carbon cycle has so far not been studied ***,urbanization might affect decomposition within urban *** far,only few studies have examined the effects of the level of urbanization on *** study addresses the influence of the level of urbanization on decomposition *** explores whether potential influences are exerted through leaf litter quality alterations or through direct effects of decomposition site’s level of *** litter of five different tree species was sampled at urban and periurban *** of this litter was analyzed in three different experiments:a climate chamber incubation,a reciprocal litterbag transplant at urban and periurban sites,and a common garden litterbag ***:Decomposition site’s level of urbanization did not show a significant ***,in all species,when significant differences were observed,leaf litter of urban origin decomposed significantly faster than leaf litter of periurban *** effect was observed in all three *** the reciprocal litter transplant experiment,62%±3%mass loss in litter of urban origin compared to 53%±3%in litter of periurban origin was *** difference was not as pronounced in the other two experiments,with 94%±1%mass loss of litter originating in urban habitats compared to 92%±1%mass loss of litter originating in periurban habitats in the common garden experiment and 225±13 mg CO2 released from litter originating in urban habitats compared to 200±13 mg CO2 released from litter originating in periurban habitats in the climate chamber ***:We conclude that the level of urbanization affects decomposition indirectly through alterations in leaf litter quality even over short urban to periurban distances.

关键词： Litterbags Urban gradients Carbon cycling Mass loss Respiration Urban ecology Urban forests Paired studies Suburban Urban–rural contrast

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Early dynamics in plant community trait responses to a novel, more extreme hydrological gradient

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Journal of Plant Ecology 2019年第2期12卷 327-335页

作者： Andrea Oddershede Cyrille Violle annette Baattrup-Pedersen jens-Christian Svenning Christian Damgaard Section for Plant and Insect Ecology Department of BioscienceAarhus UniversityVejlsøvej 25DK-8600 SilkeborgDenmark Section for Ecoinformatics&Biodiversity Department of BioscienceAarhus UniversityNy Munkegade 114DK-8000 Aarhus CDenmark CEFE UMR 5175 CNRS-Universitéde Montpellier-UniversitéPaul-Valéry MontpellierEPHE-1919 route de MendeF-34293 MontpellierCEDEX 5France Section for Stream and Wetland Ecology Department of BioscienceAarhus UniversityVejlsøvej 25DK-8600 SilkeborgDenmark

Aims For temperate regions such as northern Europe,predicted climate change patterns include an increase in winter precipitation causing increased risk of flooding,whereas periods of droughts will become more frequent in *** aim of this study is to explore vari-ations in plant functional trait distributions along a hydrological gradient spanning from recurrent drought events to recurrent flood-ing-mimicking future precipitation *** The experiment was conducted in a controlled grassland experi-ment over a period of 3 years.A novel and more extreme hydro-logical regime was achieved by manipulating the flow of a nearby stream thereby creating a continuous hydrological gradient from flooding during winter to drought during *** commu-nity responses were recorded along this hydrological ***-weighted trait distribution changes along the gradient were described using null *** functional traits were con-sidered:seed mass,leaf dry matter content(LDMC),leaf area,leaf thickness,specific leaf area(SLA)and *** findings Over time,responses in plant functional traits changed at the community *** the study period consistent changes occurred in the mean trait value of several *** in relatively dry plots became dominated by species with water-conserving life strategies,represented by high seed mass and thick *** contrast,disturbance-resistant species(high leaf dry matter content)became dominant in flooded plots,indicating that persistence to flooding was the most important factor control-ling the functional structure in those ***,a high abundance of small-seeded species in flooded plots likely indicates higher frequency of species with higher dispersal ability through *** conclusion,plant traits are useful for predicting responses to climate change,but abrupt and extreme climate event may cause unexpected responses because they have no analog to previously more sta

关键词： functional diversity trait-environment relationship hydrology extreme events flooding

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Fully integrated and broadband Si-rich silicon nitride wavelength converter based on Bragg scattering intermodal four-wave mixing

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Photonics Research 2024年第3期12卷 I0001-I0010页

作者： VALERIO VITALI THALÍA DOMÍnGUEZ BUCIO HAO LIU JOSÉMAnUEL LUQUE GOnZÁLEZ FRAnCISCO JURADO-ROMERO ALEJAnDRO ORTEGA-MOÑUX GLEnn CHURCHILL JAMES C.GATES JAMES HILLIER nIKOLAOS KALFAGIAnnIS DAnIELE MELATI jens H.SCHMID ILARIA CRISTIAnI PAVEL CHEBEn J.GOnZALO WAnGÜEMERT-PÉREZ ÑIGO MOLInA-FERnÁnDEZ FREDERIC GARDES COSIMO LACAVA PERIKLIS PETROPOULOS Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK Electrical Computer and Biomedical Engineering DepartmentUniversity of PaviaPavia 27100Italy Telecommunication Research Institute(TELMA) Universidad de MálagaCEI Andalucı´a TECHE.T.S.I.Telecomunicación29010 MálagaSpain School of Science and Technology Nottingham Trent UniversityNottingham NG118NSUK Department of Electrical Engineering Eindhoven University of TechnologyEindhoven 5600 MBThe Netherlands Department of Materials Science and Engineering University of IoanninaIoannina 45110Greece Centre de nanosciences et de nanotechnologies UniversitéParis-SaclayCNRS91120 PalaiseauFrance Advanced Electronics and Photonics Research Center National Research Council CanadaOttawaOntario K1A 0R6Canada

Intermodal four-wave mixing(FWM)processes have recently attracted significant interest for all-optical signal processing applications thanks to the possibility to control the propagation properties of waves exciting distinct spatial modes of the same *** allows,in principle,to place signals in different spectral regions and satisfy the phase matching condition over considerably larger bandwidths compared to intramodal ***,the demonstrations reported so far have shown a limited bandwidth and suffered from the lack of on-chip components designed for broadband manipulation of different *** demonstrate here a silicon-rich silicon nitride wavelength converter based on Bragg scattering intermodal FWM,which integrates mode conversion,multiplexing and de-multiplexing functionalities *** system enables wavelength conversion between pump waves and a signal located in different telecommunication bands(separated by 60 nm)with a 3 dB bandwidth exceeding 70 nm,which represents,to our knowledge,the widest bandwidth ever achieved in an intermodal FWM-based system.

关键词： scattering pump modal

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new design paradigm for heterogeneous catalysts

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national Science Review 2015年第2期2卷 140-143页

作者： Aleksandra Vojvodic jens K.n?rskov SUnCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory Department of Chemical Engineering Stanford University

Both scientiic discovery and technological development are at some point faced with the question of how to progress from a trial-and-error approach to a highly controlled design *** heterogeneous catalysis,the search for the optimal active site of a catalyst for a given chemical reaction has been the central objective of research for almost a ***

关键词： new design paradigm for heterogeneous catalysts

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Predicting aqueous stability of solid with computed Pourbaix diagram using SCAn functional

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npj Computational Materials 2020年第1期6卷 343-349页

作者： Zhenbin Wang Xingyu Guo Joseph Montoya jens K.nørskov CatTheory Department of PhysicsTechnical University of Denmark2800 Kongens LyngbyDenmark Materials Science and Engineering Program University of California San Diego9500 Gilman DrLa JollaCA 92093USA Toyota Research Institute Los AltosCA 94022USA

In this work,using the SCAn functional,we develop a simple method on top of the Materials Project(MP)Pourbaix diagram framework to accurately predict the aqueous stability of *** extensively evaluate the SCAn functional’s performance in computed formation enthalpies for a broad range of oxides and develop Hubbard U corrections for transition-metal oxides where the standard SCAn functional exhibits large *** performance of the calculated Pourbaix diagram using the SCAn functional is validated with comparison to the experimental and the MP PBE Pourbaix diagrams for representative *** indicate the SCAn Pourbaix diagram systematically outperforms the MP PBE in aqueous stability *** further show applications of this method in accurately predicting the dissolution potentials of the state-of-the-art catalysts for oxygen evolution reaction in acidic media.

关键词： diagram stability functional

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利用择形分子筛异构化亚甲基二苯胺

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Chinese Journal of Catalysis 2024年第7期62卷 124-130页

作者： Sam Van Minnebruggen Ka Yan Cheung Trees De Baerdemaeker niels Van Velthoven Matthias Degelin Galahad O’Rourke Hiroto Toyoda Andree Iemhoff Imke Muller Andrei-nicolae Parvulescu Torsten Mattke jens Ferbitz 吴勤明肖丰收 Toshiyuki Yokoi nils Bottke Dirk De Vos 巴斯夫股份有限公司膜分离、吸附、催化和光谱学可持续解决方案中心(cMACS) 比利时巴斯夫股份有限公司研究组德国东京工业大学纳米空间催化研究所横滨日本浙江大学化学系浙江杭州310028

亚甲基二苯胺(MDA)被广泛用作生产聚氨酯和聚异氰脲酸酯的中间体.然而,当前MDA的生产工艺在控制(4,4’/(2,4’+2,2’))异构体比例方面还存在局限.其中,4,4’-MDA被认为是最有价值的异构体.尽管2,4'-MDA在市场上也有一定的需求,但如果能... 详细信息

亚甲基二苯胺(MDA)被广泛用作生产聚氨酯和聚异氰脲酸酯的中间体.然而,当前MDA的生产工艺在控制(4,4’/(2,4’+2,2’))异构体比例方面还存在局限.其中,4,4’-MDA被认为是最有价值的异构体.尽管2,4'-MDA在市场上也有一定的需求,但如果能将其有效地转化为4,4'-MDA,将能显著提升其附加值.本文在使用苯胺的条件下,利用β分子筛等催化剂,通过双分子机制,可以选择性地将2,4'-MDA异构化为4,4'-MDA.尽管实验显示,多种酸性沸石具有较高的异构化活性,但MCM-68(具有MSE拓扑结构)的催化性能尤为出色,它不仅展现出高异构化活性,而且具有很好的选择性.MCM-68主要催化2,4'-MDA异构化为4,4'-MDA,而2,2'-MDA和低聚物的形成则可以忽略不计.本文还深入探讨了该择形作用的原因,并详细研究了酸位置在MSE分子筛孔道限制中的关键作用.

关键词：铝分布多相催化异构化亚甲基二苯胺聚氨酯择形

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Combined inhibitors of angiogenesis and histone deacetylase:Efficacy in rat hepatoma

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World Journal of Gastroenterology 2011年第31期17卷 3623-3629页

作者： Marion Ganslmayer annette Zimmermann Steffen Zopf Christoph Herold Medical Department 1 University hospital Erlangen-Nuernberg Department of Otolaryngology University of Marburg

AIM:To evaluate the antitumoral effect of combined inhibitors of angiogenesis and histone deacetylases in an experimental rat hepatoma ***:MH7777A hepatoma cells were injected into the liver of male Buffalo *** 7 d treatment with the vascular endothelial growth factor receptor antagonist PTK787/ZK222584(PTK/ZK),the histone deacetylase inhibitor MS-275,tamoxifen(TAM) and/or retinoic acid was initiated(n ≥ 8 animals/group).natural tumor development was shown in untreated control groups(control 1 with n = 12,control 2 with n = 8).The control groups were initiated at different time points to demonstrate the stability of the hepatoma *** documentation of possible side effects,we documented any change in body weight,loss of fur and *** 21 d treatment,the rats were *** target parameters were tumor size and metastasis ***,immunohistochemistry for the proliferating cell nuclear antigen(PCnA) and TdT-mediated dUTP-biotin nick end labeling(TUnEL) assay were ***:The control groups developed large tumor nodules with extrahepatic tumor burden in the lung and abdominal organs(control 1:6.18 cm3 ± 4.14 cm3 and control 2:8.0 cm3 ± 4.44 cm3 28 d after tumor cell injection).The tumor volume did not differ significantly in the control groups(P = 0.13).As single agents MS-275 and PTK/ZK reduced tumor volume by 58.6% ± 2.6% and 48.7% ± 3.2% vs control group 1,which was significant only for MS-275(P = 0.025).The combination of MS-275 and PTK/ZK induced a nearly complete and highly significant tumor shrinkage by 90.3% ± 1%(P = 0.005).Addition of TAM showed no further efficacy,while quadruple therapy with retinoic acid increased antitumoral efficacy(tumor reduction by 93 ± 1%) and side *** positive cells were not significantly reduced by the single agents,while dual therapy(MS-275 and PTK/ZK) and quadruple therapy reduced the PCnA-positive cell fraction significantly by 9.1 and 20.6% vs control 1(P < 0.05).Th

关键词： PTK787 ZK222584 MS-275 Hepatocellular carcinoma Histone deacetylase inhibitor

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Resolvent Estimates and Quantification of nonlinear Stability

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Acta Mathematica Sinica,English Series 2000年第1期16卷 1-20页

作者： Heinz-Otto Kreiss jens Lorenz Department of Mathematics UCLALos AngelesCA 90095USA Department of Mathematics and Statistics UNMAlbuquerqueNM 87131USA

The aim of this paper is to clarify the role played by resolvent estimates for nonlinear *** will give examples showing that a large resolvent may lead to a small domain of nonlinear *** other examples the resolvent is large,but the domain of nonlinear stability is completely *** case prevails depends on the details of the problem. We will also show that the size of the resolvent depends in an essential way on the norms that are used.

关键词： Resolvent estimates nonlinear stability Pseudospectrum Convection-dominated flow

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