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Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期68卷 308-316页

作者： Sili Wang Jiancheng Huang Yanan Du Wei Huang Yufeng xue Xiaokun Xu Guannan Zhong yuanyuan shi Bin Hong Xiaoying Bian wen Liu State Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

关键词： cbl-dependent radical SAM protein biosynthesis chuangxinmycin stereoselective methylation

3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： Ke Yao Gaoying Hong Ximin yuan Weicheng Kong Pengcheng Xia yuanrong Li Yuewei Chen Nian Liu Jing he Jue shi Zihe Hu Yanyan Zhou Zhijian Xie Yong he State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

Drosophila models used to simulate human ATP1A1 gene mutations that cause Charcot-Marie-Tooth type 2 disease and refractory seizures

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Neural Regeneration Research 2025年第1期20卷 265-276页

作者： Yao yuan Lingqi Yu Xudong Zhuang Dongjing wen Jin he Jingmei Hong Jiayu Xie Shengan Ling Xiaoyue Du wenfeng Chen Xinrui Wang Institute of Life Sciences College of Biological Science and EngineeringFuzhou UniversityFuzhouFujian ProvinceChina NHC Key Laboratory of Technical Evaluation of Fertility Regulation for Non-human Primate(Fujian Maternity and Child health Hospital) FuzhouFujian ProvinceChina Medical Research Center Fujian Maternity and Child Health HospitalCollege of Clinical Medicine for Obstetrics&Gynecology and PediatricsFujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurology and Institute of Neurology of The First Affiliated Hospital Institute of Neuroscienceand Fujian Key Laboratory of Molecular NeurologyFujian Medical UniversityFuzhouFujian ProvinceChina

Certain amino acids changes in the human Na^(+)/K^(+)-ATPase pump,ATPase Na^(+)/K^(+)transporting subunit alpha 1(ATP1A1),cause Charcot-Marie-Tooth disease type 2(CMT2)disease and refractory *** develop in vivo models to study the role of Na^(+)/K^(+)-ATPase in these diseases,we modified the Drosophila gene homolog,Atpα,to mimic the human ATP1A1 gene mutations that cause *** located within the helical linker region of human ATP1A1(I592T,A597T,P600T,and D601F)were simultaneously introduced into endogenous Drosophila Atpαby CRISPR/Cas9-mediated genome editing,generating the Atpα^(TTTF)*** addition,the same strategy was used to generate the corresponding single point mutations in flies(Atpα^(I571T),Atpα^(A576T),Atpα^(P579T),and Atpα^(D580F)).Moreover,a deletion mutation(Atpα^(mut))that causes premature termination of translation was generated as a positive *** these alleles,we found two that could be maintained as homozygotes(Atpα^(I571T)and Atpα^(P579T)).Three alleles(Atpα^(A576T),Atpα^(P579)and Atpα^(D580F))can form heterozygotes with the Atpαmut *** found that the Atpαallele carrying these CMT2-associated mutations showed differential phenotypes in *** heterozygous for Atpα^(TTTF)mutations have motor performance defects,a reduced lifespan,seizures,and an abnormal neuronal *** Drosophila models will provide a new platform for studying the function and regulation of the sodium-potassium pump.

关键词： ATP1A1 Atpα bang-sensitive paralysis Charcot-Marie-Tooth disease type 2 CRISPR/Cas9 homology-directed repair Na^(+)/K^(+)-ATPase point mutation seizures sodium pump

Wafer‑Scale Ag_(2)S‑Based Memristive Crossbar Arrays with Ultra‑Low Switching‑Energies Reaching Biological Synapses

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Nano-Micro Letters 2025年第3期17卷 328-339页

作者： yuan Zhu Tomas Nyberg Leif Nyholm Daniel Primetzhofer Xun shi Zhen Zhang Division of Solid‑State Electronics Department of Electrical EngineeringUppsala University75121 UppsalaSweden Department of Chemistry Uppsala UniversityUppsalaSweden Department of Physics and Astronomy Uppsala UniversityUppsalaSweden State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China

Memristive crossbar arrays(MCAs)offer parallel data storage and processing for energy-efficient neuromorphic ***,most wafer-scale MCAs that are compatible with complementary metal-oxide-semiconductor(CMOS)technology still suffer from substantially larger energy consumption than biological synapses,due to the slow kinetics of forming conductive paths inside the memristive *** we report wafer-scale Ag_(2)S-based MCAs realized using CMOS-compatible processes at temperatures below 160℃.Ag_(2)S electrolytes supply highly mobile Ag+ions,and provide the Ag/Ag_(2)S interface with low silver nucleation barrier to form silver filaments at low energy *** further enhancing Ag+migration in Ag_(2)S electrolytes via microstructure modulation,the integrated memristors exhibit a record low threshold of approximately−0.1 V,and demonstrate ultra-low switching-energies reaching femtojoule values as observed in biological *** low-temperature process also enables MCA integration on polyimide substrates for applications in flexible ***,the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training *** impressive accuracy of 92.6%in image recognition simulations is demonstrated with the MCAs after the *** demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag_(2)S films Reactive sputter Silver nucleation Ag^(+)migration Energy-efficient neuromorphic computing

Mechanical Properties of Railway High-strength Manufactured Sand Concrete: Typical Lithology, Stone Powder Content and Strength Grade

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 194-203页

作者： WANG Zhen LI Huajian HUANG Fali YANG Zhiqiang wen Jiaxin shi henan Railway Engineering Research Institute China Academy of Railway Science Corporation LimitedBeijing 100081China State Key Laboratory for Track Technology of High-Speed Railway Beijing 100081China

In order to achieve the large-scale application of manufactured sand in railway high-strength concrete structure,a series of high-strength manufactured sand concrete(HMC)are prepared by taking the manufactured sand lithology(tuff,limestone,basalt,granite),stone powder content(0,5%,10%,15%)and concrete strength grade(C60,C80,C100)as *** evolution of mechanical properties of HMC and the correlation between cubic compressive strength and other mechanical properties are *** to river sand,manufactured sand enhances the cubic compressive strength,axial compressive strength and elastic modulus of concrete,while its potential microcracks weaken the flexural strength and splitting tensile strength of *** powder content displays both positive and negative effects on mechanical properties of HMC,and the stone powder content is suggested to be less than 10%.The empirical formulas between cubic compressive strength and other mechanical properties are proposed.

关键词： manufactured sand concrete railway mechanical property lithology stone powder content

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第1期68卷 201-208页

作者： Hui-Feng Wang wen-Jie shi Yu-Xin Yang Bao-Xia Dong Tong-Bu Lu Di-Chang Zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

关键词： metal-organic frameworks dinuclear metal centers synergistic catalysis CO2 reduction photocatalysis

Identification of a dual functional betulinic acid analog for the treatment of osteoarthritis by phenotypic screening

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Science China Life Sciences 2025年第1期68卷 300-302页

作者： Ze-Min Lin Mai Xiang wen-Hui Wei Shu-Hui Fan Li Chen Jie Wang Xiao-Qian Yang Chun-Hao Yang shi-Jun he Jian-Ping Zuo Laboratory of Immunopharmacology State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences School of Pharmacy University of Chinese Academy of Sciences School of Pharmacy Nanjing University of Chinese Medicine State Key Laboratory of Drug Research Department of Medicinal ChemistryShanghai Institute of Materia MedicaChinese Academy of Sciences Innovation Research Institute of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine Experiment Center for Science and Technology Shanghai University of Traditional Chinese Medicine

Dear Editor, Phenotypic drug discovery, which observes compound effects on physiology,has given way to targeting specific molecules, but has revived by using modern methods to find drugs based on therapeutic outcomes in disease models(Vincent et al., 2022). Osteoarthritis(OA) is a prevalent chronic joint disorder, primarily affecting knee joints, with osteoclast activation due to low-grade inflammation resulting in increased bone resorption and structural changes in the joint(Katz et al.,2021).

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A Mn-porphyrinic metal–organic framework immobilizing glucose oxidase for combined photodynamic/chemodynamic/starvation therapy

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Tungsten 2025年第1期7卷 183-194页

作者： Xin-Ran Sun Hao-Ming yuan Guo-Da Zhang Chao Wang Shu-Juan Sun Peng-Fei shi Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers School of Chemistry and Chemical Engineering Linyi University

The combination of photodynamic therapy（PDT） and chemodynamic therapy（CDT） in tumor treatment has attracted considerable ***,tumor hypoxia and glutathione（GSH） overproduction in the tumor tissue restricted the progress of their ***,a Mn-porphyrinic metal-organic framework（Mn-TCPP） was constructed by the one-pot method and further used for immobilizing glucose oxidase（GOx） to obtain GOx@*** would rapidly exhaust endogenous glucose into hydrogen peroxide（H2O2） and gluconic acid,thus shutting off the energy supply of tumor cells for starvation ***-TCPP catalyzed H2O2to produce oxygen,regulating the hypoxic tumor microenvironment and in turn improving1O2generation under laser ***,Mn-TCPP can reduce reactive oxygen species consumption owing to the redox reaction between Mn3+and GSH,thus greatly enhancing ***,benefiting from GOx-mediated starvation therapy,Mn2+produced by Mn3+reduction can react with sufficient intracellular H2O2to generate ·OH with high cytotoxicity through a Fenton-like *** treatment by GOx@Mn-TCPP under laser irradiation in vitro,the cell viability of 4T1 and A549 tumor cells reached to 20%,reflecting GOx@Mn-TCPP could give full play to the advantages of PDT/CDT/starvation *** results in vivo demonstrated that GOx@Mn-TCPP mediated synergistic cascade therapy could significantly inhibit tumor growth and improve the therapeutic effect.

关键词： Chemodynamic therapy Immobilizing enzyme Metal–organic frameworks Photodynamic therapy Starvation therapy

Recent progress in metal-organic frameworks(Part II—material application)

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Science China Chemistry 2025年

作者： Jiandong Pang wentao Jiang xue-wen Zhang Hao-Long Zhou Yuxiu Sun Wei Gong Bin Wang Fuyin Ma Linwei he Long Chen Qiang Chen he-Qi Zheng yuanjing Cui wen-Jie shi Chao Zhang Mei Wang Yue-Biao Zhang Jie-Peng Zhang Chongli Zhong Yong Cui Shuao Wang Jian-Rong Li Guodong Qian Tong-Bu Lu Huan Pang Xian-he Bu Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology School of Chemistry and Chemical Engineering Yangzhou University School of Materials Science and Engineering Nankai University School of Physical Science and Technology ShanghaiTech University MOE Key Laboratory of Bioinorganic and Synthetic Chemistry GBRCE for Functional Molecular Engineering School of Chemistry IGCMESun Yat-sen University Department of Chemistry Shantou University School of Chemical Engineering and Technology Tiangong University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences Soochow University College of Materials Science & Engineering Beijing University of Technology State Key Laboratory of Silicon and Advanced Semiconductor Materials Cyrus Tang Center for Sensor Materials and ApplicationsSchool of Materials Science & Engineering Zhejiang University

As a class of functional crystalline porous materials, metal-organic frameworks(MOFs) gained rapid development in the past three decades and a large number of MOFs with ordered structures, high surface areas, and functionalized channels have been investigated. MOFs and MOF-derived/composite materials show great potential in many application fields. In this review, we discussed the main applications of MOFs and MOF-derived/composite materials in small molecule storage, separation, luminescence, sensing, multitype catalysis, and energy storage. In addition, challenges and problems in the future research of MOFsrelated fields are also discussed.

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