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Synthetic and Systems Biotechnology 2024年第1期9卷 127-133页

作者： Hu Li Wei Li Kaihui Song Yu Liu Guiyun Zhao yi-ling du Polytechnic Institute Zhejiang UniversityHangzhou310022China Department of Microbiology Zhejiang University School of MedicineHangzhou310058China College of Life Sciences Zhejiang University310058HangzhouChina

The biological signaling molecule nitric oxide(NO)has recently emerged as a metabolic precursor for the creation of microbial natural products with diversified structures and biological *** the biosynthetic gene clusters(BGCs)of these compounds,genes associated with NO production pathways have been *** this study,we employ a nitric oxide synthase(NOS)-guided genome mining strategy for the targeted discovery of NO-derived bacterial natural products and NO-utilizing *** show that a conserved NOS-containing BGC,distributed across several actinobacterial genomes,is responsible for the biosynthesis of lajollamycin,a unique nitro-tetraene-containing antibiotic whose biosynthetic mechanism remains *** a combination of in vivo and in vitro studies,we unveil the first cytochrome P450 enzyme capable of catalyzing olefin nitration in natural product *** results not only expand the current knowledge about biosynthetic nitration processes but also offer an efficient way for targeted identification of NO-utilizing metabolic pathways and novel nitrating biocatalysts.

关键词： Nitric oxide Genome mining Biosynthesis Nitration Cytochrome P450

Rational and semi-rational engineering of cytochrome P450s for biotechnological applications

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Synthetic and Systems Biotechnology 2018年第4期3卷 283-290页

作者： Lian-Hua Xu yi-ling du College of Life Sciences Zhejiang Sci-Tech UniversityHangzhou 310018China Institute of Pharmaceutical Biotechnology The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310058China

The cytochrome P450 enzymes are ubiquitous heme-thiolate proteins performing regioselective and stereoselective oxygenation reactions in cellular *** to their broad substrate scope and catalytic versatility,P450 enzymes are also attractive candidates for many industrial and biopharmaceutical *** particular uses,enzyme properties of P450s can be further optimized through directed evolution,rational,and semi-rational engineering approaches,all of which introduce mutations within the P450 *** this review,we describe the recent applications of these P450 engineering approaches and highlight the key regions and residues that have been identified using such ***“hotspots”lie within critical functional areas of the P450 structure,including the active site,the substrate access channel,and the redox partner interaction interface.

关键词： Cytochrome P450 Protein engineering Rational design Crystal structure

Targeted genome mining for microbial antitumor agents acting through DNA intercalation

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Synthetic and Systems Biotechnology 2023年第3期8卷 520-526页

作者： Zhijie Zhao Guiyun Zhao yi Chai Wei Li Kaihui Song Wenbin Zhao Hairong Li Miaolian Wu Zhan Zhou yi-ling du The Fourth Affiliated Hospital and Department of Microbiology School of MedicineZhejiang UniversityHangzhou310058China Yong Loo Lin School of Medicine National University of SingaporeSingapore Innovation Institute for Artificial Intelligence in Medicine College of Pharmaceutical SciencesZhejiang UniversityHangzhou310058China The Fourth Affiliated Hospital School of MedicineZhejiang UniversityYiwu322000China Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering Hangzhou310058China

Microbial natural products have been one of the most important sources for drug *** the current postgenomic era,sequence-driven approaches for natural product discovery are becoming increasingly ***,we develop an effective genome mining strategy for the targeted discovery of microbial metabolites with antitumor *** method employs uvrA-like genes as genetic markers,which have been identified in the biosynthetic gene clusters(BGCs)of several chemotherapeutic drugs of microbial origin and confer self-resistance to the corresponding *** systematic genomic analysis of gifted actinobacteria genera,identification of uvrA-like gene-containing BGCs,and targeted isolation of products from a BGC prioritized for metabolic analysis,we identified a new tetracycline-type DNA intercalator *** results thus provide a new genome mining strategy for the efficient discovery of antitumor agents acting through DNA intercalation.

关键词： Genome mining Microbial natural product DNA intercalator UvrA-like protein Biosynthetic gene clusters Tetracycline

Renewable conversion of coal gangue to 13-X molecular sieve for Cd^(2+)-containing wastewater adsorption performance

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Rare Metals 2024年第2期43卷 702-710页

作者： Le Kang Si-Fan Liu Da-Wei yi Kai Wang Hui-ling du Hao-Qi Huang Peng Chen College of Materials Science and Engineering Xi’an University of Science and TechnologyXi’an710054China School of Electrical Engineering Weihai Innovation Research InstituteQingdao UniversityQingdao266000China School of Metallurgy Northeastern UniversityShenyang110819China School of Materials and Chemical Engineering Tongren UniversityTongren554300China

Using coal gangue(CG)as raw material,a new type of all solid-waste-based 13-X molecular sieve material was controllably prepared by alkali fusion-hydrothermal *** synthetic molecular sieve was used as a solid adsorbent to treat Cd^(2+)-containing wastewater,and its adsorption behavior on Cd^(2+)in aqueous solution was studied and *** microstructure and morphology of the molecular sieve were investigated by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM)and specific surface area *** results show that the synthesized 13-X molecular sieve has higher Brunauer–Emmett–Teller(BET)specific surface area with higher crystallinity and higher adsorption capacity for the heavy metal Cd^(2+).The adsorption process of Cd^(2+)by molecular sieve conforms to the Langmuir isotherm adsorption equation and Lagergren pseudo-second-order rate *** with thermodynamic calculation,it can be concluded that the adsorption process is physically monolayer,spontaneous and *** this study,a low-cost and naturally available synthesis method of 13-X molecular sieve is *** with its adsorption mechanism for Cd^(2+),it provides a feasible and general method for removing heavy metal ions from coal gangue and also provides a new way for the utilization of coal gangue with high added value.

关键词： Coal gangue Hydrothermal synthesis 13-X molecular sieve Adsorption Wastewater containing Cd^(2+)

Existence of long-range magnetic order in Heisenberg spin nanoribbons with edge modification

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Communications in Theoretical Physics 2024年第7期76卷 134-144页

作者： Da-cheng Ma ling-yi Cui Chu-xiao Sun Xiao-dan Chi Zheng-Nan XianYu An du College of Science Northeastern UniversityShenyang 110819China Department of Basic Science Dalian Naval AcademyDalian 116018China Department of Physics College of SciencesShenyang University of Chemical TechnologyShenyang 110142China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityChina Key Laboratory of Data Analytics and Optimization for Smart Industry(Northeastern University) Ministry of EducationChina

Long-range magnetic order appears on a side decorated Heisenberg spin nanoribbon at nonzero temperature,although no spontaneous magnetization exists in a one-or two-dimensional isotropic Heisenberg model at any nonzero temperature according to the Mermin-Wagner *** use of the spin Green's function method,we calculated the magnetizations of Heisenberg nanoribbons decorated by side spins with single-ion anisotropy and found that the system exhibits a nonzero transition temperature,whether the decorated edge spins of the system link together or separate from each *** the width of the nanoribbon achieves infinite limit,the transition temperatures of the system tend to the same finite constant eventually whether one edge or both edges are decorated by side spins in the *** results reveal that the magnetism of a low-dimensional spin system is different from that of a threedimensional spin *** the single-ion anisotropy of edge spins in a Heisenberg spin nanoribbon can be modulated by an electric field experimentally,various useful long-range magnetic orders of the system can be *** work can provide a detailed theoretical basis for designing and fabricating next-generation low-dimensional magnetic random-access memory.

关键词： Nanoribbon magnetic anisotropy long-range magnetic order Heisenberg model transition temperature

Editable semiconductor photo-electrodes for sustainable ammonia synthesis

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Nano Research 2024年第4期17卷 3107-3112页

作者： Ning Lan Kun du Erling Zhao Wei Zhao Tao ling Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education Institute of New-EnergySchool of Materials Science and EngineeringTianjin UniversityTianjin 300072China School of Materials Science and Engineering Tianjin Chengjian UniversityTianjin 300384China

Powered by an inexhaustible supply of solar energy,photoelectrochemical(PEC)nitrogen reduction reaction(NRR)provides an ideal solution for the synthesis of green ammonia(NH_(3)).Although great efforts have been made in the past decades,there are still significant challenges in increasing the NH_(3) yields of the PEC-NRR *** addition to the issues of low activity and selectivity similar to electrochemical NRR,the progress of PEC-NRR is also impeded by the limited increase in NH_(3) yields as the electrode is ***,we propose an editable electrode design strategy that parallels unit photo-electrodes to achieve a linear increase in NH_(3) yields with electrode active *** demonstrate that the editable electrode design strategy minimizes the electrode charge transfer resistance,allowing more photo-generated carriers to reach the electrode surface and promote the catalytic *** believe that this editable electrode design strategy provides an avenue to achieve sustainable PEC NH_(3) production.

关键词： editable electrode photoelectrochemical nitrogen reduction reaction parallel electrode ZnSe

Numerical study on the effective thermal conductivity and thermal tortuosity of porous media with different morphologies

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Science China(Technological Sciences) 2024年第6期67卷 1685-1694页

作者： du Shen LI Dong LI Meng-Jie HE Ya-ling Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China

Effective thermal conductivity and thermal tortuosity are crucial parameters for evaluating the effectiveness of heat conduction within porous *** direct pore-scale numerical simulation method is applied to investigate the heat conduction processes inside porous structures with different *** thermal conduction performances of idealized porous structures are directly compared with real foams across a wide range of *** foam structures are reconstructed using X-ray computed tomography and image processing techniques,while Kelvin and Weaire-Phelan structures are generated through periodic unit cell *** detailed temperature fields inside the porous structures are determined by solving the heat conduction equation at the pore *** results present that the equivalent thermal conductivity of Kelvin and Weaire-Phelan structures is similar to and greater than that of the real foam structure with the same strut *** thermal tortuosity of real foam structure is relatively larger and the heat conduction path becomes straighter by adopting the anisotropic *** thermal tortuosity of the fluid channels for Kelvin,Weaire-Phelan,and real foam structures is close to *** thermal conductivity of porous structures with heat transfer fluid increases as the thermal conductivity ratio of fluid to solid becomes larger.A small porosity of porous media leads to a larger equivalent thermal conductivity due to the dominant contribution of porous skeleton in the heat conduction *** derived from parallel and series models,as well as the Maxwell-Eucken models,provide decent predictions of effective thermal conductivity,with an average error of less than 8%in the entire range of thermal conductivity ratio.

关键词： volumetric solar receiver porous morphology direct pore-scale simulation equivalent thermal conductivity thermal tortuosity empirical correlation

New black-to-white hole solutions with improved geometry and energy conditions

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 30-43页

作者： Zhongwen Feng yi ling Xiaoning Wu Qingquan Jiang School of Physics and Astronomy China West Normal UniversityNanchong 637009China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics University of Chinese Academy of SciencesBeijing 100049China Institute of Mathematics Academy of Mathematics and System Science and Hua Loo-Keng Key Laboratory of MathematicsChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100190China

We construct new black-to-white hole solutions which connect the geometry of spacetime at some gluing surface inside the *** continuity of the metric can be guaranteed up to the arbitrary order which is controlled by the power factor *** sort of black-to-white holes is characterized by the sub-Planckian scalar curvature,independent of the mass of black-to-white *** importantly,we show that the energy condition is only violated within a small region near the gluing *** geodesics of particles within the region from black hole to white hole is also *** turns out that the matter falling into the black hole may pass through the center without singularity and come out from the white *** scenario provides novel ideas for understanding the information loss paradox in traditional black hole physics.

关键词： regular black hole energy condition singularity quantum gravity

Automated Identification of Ordered Phases for Simulation Studies of Block Copolymers

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Chinese Journal of Polymer Science 2024年第5期42卷 683-692,I0011页

作者： Yu-Chen Zhang Wei-ling Huang yi-Xin Liu State Key Laboratory of Molecule Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China

In unit cell simulations,identification of ordered phases in block copolymers(BCPs)is a tedious and time-consuming task,impeding the advancement of more streamlined and potentially automated research *** this study,we propose a scattering-based automated identification strategy(SAIS)for characterization and identification of ordered phases of BCPs based on their computed scattering *** approach leverages the scattering theory of perfect crystals to efficiently compute the scattering patterns of periodic morphologies in a unit *** the first stage of the SAIS,phases are identified by comparing reflection conditions at a sequence of Miller *** confirm or refine the identification results of the first stage,the second stage of the SAIS introduces a tailored residual between the test phase and each of the known candidate ***,our strategy incorporates a variance-like criterion to distinguish background species,enabling its extension to multi-species BCP *** has been demonstrated that our strategy achieves exceptional accuracy and robustness while requiring minimal computational ***,the approach allows for real-time expansion and improvement to the candidate phase library,facilitating the development of automated research workflows for designing specific ordered structures and discovering new ordered phases in BCPs.

关键词： Block copolymer Phase identification Scattering function

Mechanism of pachymic acid in the treatment of gastric cancer based on network pharmacology and experimental verification

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 30-50页

作者： Yu-Hua du Jian-Jun Zhao Xia Li Shi-Cong Huang Na Ning Guo-Qing Chen yi Yang yi Nan ling Yuan College of Pharmacy Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Ningxia Chinese Medicine Research Center Manufacturing LaboratoryYinchuan 750004Ningxia Hui Autonomous RegionChina College of Foundation Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Key Laboratory of Ningxia Minority Medicine Modernization Ministry of Education Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina

BACKGROUND Pachymic acid(PA)is derived from Poria *** has a variety of pharmacological and inhibitory effects on various ***,the mechanism of action of PA in gastric cancer(GC)remains *** To investigate the mechanism of PA in treating GC via the combination of network pharmacology and experimental *** The GeneCards and OMIM databases were used to derive the GC targets,while the Pharm Mapper database provided the PA *** the STRING database,a protein-protein interaction network was constructed and core targets were *** analyses of Gene Ontology,Kyoto Encyclopedia of Genes and Genomes(KEGG),and gene set enrichment analysis were conducted,and molecular docking and clinical correlation analyses were performed on the core ***,the network pharmacology findings were validated through in vitro cell assays,encompassing assessments of cell viability,apoptosis,cell cycle,cloning,and western blot *** According to network pharmacology analysis,the core targets were screened,and the PI3K/AKT signaling pathway is likely to be the mechanism by which PA effectively treats GC,according to KEGG enrichment *** experimental findings showed that PA could control PI3K/AKT signaling to prevent GC cell proliferation,induce apoptosis,and pause the cell *** Network pharmacology demonstrated that PA could treat GC by controlling a variety of signaling pathways and acting on a variety of *** has also been supported by in vitro cell studies,which serve as benchmarks for further research.

关键词： Pachymic acid Gastric cancer Network pharmacology Enrichment analysis Cell proliferation