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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 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.

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Morphology and molecular phylogeny of three black corals(Antipatharia,Schizopathidae)from seamounts in the Western Pacific Ocean,with description of a new species

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Journal of Oceanology and limnology 2021年第5期39卷 1740-1757页

作者： Ting lÜ Zifeng ZHAN Kuidong xu laboratory of Marine Organism Taxonomy and Phylogeny Shandong Province Key Laboratory of Experimental Marine BiologyInstitute of OceanologyCenter for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China laboratory for Marine Biology and Biotechnology Pilot NationalLaboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

Three deep-sea black corals belonging to the family Schizopathidae,are reported from two seamounts on the Caroline Ridge in the tropical Western Pacific:Umbellapathes parva *** depth of 1488-1766 m,Telopathes *** MacIsaac&Best,2013 with depth of 937-1016 m,and Stauropathes ***(Roule,1905)with depth of 942-1353 *** latter two species are the first records in the Western Pacific *** *** characterized by monopodial corallum,relatively long unpinnulated stalk with complex pinnulated branche s developing from the lowermost primary pinnules and small spine *** differs from two known congeners by much smaller spine s and the present of secondary *** MacIsaac&Best,2013 has sparsely branched corallum,relatively long and simple pinnules arranged in subopposite or alternate ***(Roule,1905)is characterized by the corallum with almost planar pinnulated branches,and pinnules arranged in subopposite *** results indicate that the corallum size and shape are variable in conspecific specimens particularly those at different growth *** contrast,the size of the polypar spines as well as the abpolypar spines have little variation and can be served as a main differing feature for schizopathid *** phylogenetic analyses using nuclear internal transcribed spacer region(spanning partial 18 S rDNA,ITS 1,5.8 S,ITS2,and partial 28 S rDNA)and two mitochondrial fragments cox3-IGR-coxl(COI)and trnW-IGR-nad2(NAD2)showed Telopathes,Stau ropathes,and Bathypathes had close relationships,and Umbellapathes formed a sister clade with Alternatipathes.

关键词： Anthozoa black coral new species seamount taxonomy Western Pacific

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A Practical Predefined-Time Stability Criterion and Its Application to Uncertain Nonlinear Systems

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Journal of Systems Science & Complexity 2024年第6期37卷 2556-2578页

作者： xu Hao YU Dengxiu SUI Shuai xu Bowen CHEN C.l.Philip Unmanned System Research Institute Northwestern Polytechnical UniversityXi'an 710072China College of Science Liaoning University of TechnologyJinzhou 121001China School of Artificial Intelligence Optics and ElectronicsNorthwestern Polytechnical UniversityXi'an 710072China School of Computer Science and Engineering South China University of Technology and Pazhou LabGuangzhou 510641China

In this paper,the singularity-free predefined-time fuzzy adaptive tracking control problem is studied for non-strict feedback(NSF)nonlinear systems considering mismatched external *** innovative practical predefined-time stability(PPTS)criterion is proposed to provide the theoretical basis for subsequent control *** to the existing predefined-time stability(PTS)criterion,this criterion has a broader application range and can solve the control design issues of nonlinear systems with system *** logic systems(FlSs)are employed to identify unknown nonlinear *** on the backstepping control technology,a singularity-free predefined-time control(PTC)design method is proposed,in which the hyperbolic tangent function is utilized to avoid the singular problem,and the nature of fuzzy basis function is adopted to resolve the algebraic loop *** PPTS of the closed-loop NSF nonlinear system is proven with the lyapunov theory and the proposed PPTS ***,the efficiency of the presented PTC design method is verified by several sets of simulations on a single link manipulator system.

关键词： Fuzzy adaptive control nonlinear systems practical predefined-time stability predefinedtime control singularity-free control

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Functional characterization of a novel somatic oncogenic mutation of PIK3CB

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Signal Transduction and Targeted Therapy 2017年第1期2卷 1-9页

作者： Andrew D Whale lucy Colman letitia lensun Helen l Rogers Stephen J Shuttleworth Karus Therapeutics ltd. Genesis BuildingLibrary AvenueHarwell CampusOxfordshireUK

Class I phosphoinositide 3-kinase(PI3K)enzymes have attracted considerable attention as drug targets in cancer therapy over the last 20 *** signaling pathway triggered by class I PI3Ks is dysregulated in a range of tumor types,impacting cell proliferation,survival and *** oncogenic mutations of PIK3CA have previously been *** contrast,reports of PIK3CB mutations have been limited;however,in most cases,those that have been identified have been shown to be activating and *** functional characterization of a PIK3CB catalytic domain mutant,p110β^(E1051K),first discovered by others in castrateresistant prostate cancer(mCRPC),is outlined in this report;our data suggest that p110β^(E1051K)is a gain-of-function mutation,driving PI3K signaling,tumorigenic cell growth and *** cells expressing p110β^(E1051K)are sensitive to p110βinhibition;its characterization as an oncogenic driver adds to the rationale for targeting p110βand indicates a continuing need to further develop specific PI3K inhibitors for clinical development in cancer therapy.

关键词： PIK3CB PIK3CA characterization

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Extragalactic dispersion measures of fast radio bursts

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Research in Astronomy and Astrophysics 2015年第10期15卷 1629-1638页

作者： Jun xu J.l.Han National Astronomical Observatories Chinese Academy of Sciences

Fast radio bursts show large dispersion measures, much larger than the Galactic dispersion measure foreground. Therefore, they evidently have an extragalac- tic origin. We investigate possible contributions to the dispersion measure from host galaxies. We simulate the spatial distribution of fast radio bursts and calculate the dis- persion measures along the sightlines from fast radio bursts to the edge of host galaxies by using the scaled NE2001 model for thermal electron density distributions. We find that contributions to the dispersion measure of fast radio bursts from the host galaxy follow a skew Gaussian distribution. The peak and the width at half maximum of the dispersion measure distribution increase with the inclination angle of a spiral galaxy, to large values when the inclination angle is over 70~. The largest dispersion measure produced by an edge-on spiral galaxy can reach a few thousand pc cm-3, while the dispersion measures from dwarf galaxies and elliptical galaxies have a maximum of only a few tens of pc cm-3. Notice, however, that additional dispersion measures of tens to hundreds of pc cm-3 can be produced by high density clumps in host galaxies. Simulations that include dispersion measure contributions from the large Magellanic Cloud and the Andromeda Galaxy are shown as examples to demonstrate how to ex- tract the dispersion measure from the intergalactic medium.

关键词： galaxies: ISM -- radio continuum: ISM -- ISM: general

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Integration of perioperative features and intragraft TCF7l2 expression to predict lipid metabolic disorder in liver transplant recipients

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Science China life Sciences 2025年第1期 297-299页

作者： Junbin Zhou Rongli Wei Guanghan Fan Zhengxing lian xuanyu Zhang linsong Tang Zhetuo Qi Haiyang Xie Shusen Zheng Qiang Wei Xiao xu Department of Hepatobiliary and Pancreatic Surgery People's Hospital of LishuiAffiliated Lishui Hospital of Wenzhou Medical UniversityThe First Affiliated Hospital of Lishui University NHFPC Key laboratory of Combined Multi-Organ Transplantation Key laboratory of Integrated Oncology and Intelligent Medicine of Zhejiang Province Department of Hepatobiliary and Pancreatic SurgeryHangzhou First People's Hospital Department of Hepatobiliary and Pancreatic Surgery The First Affiliated HospitalZhejiang University School of Medicine Department of Urology The Second Affiliated HospitalZhejiang University School of Medicine Department of Hepatobiliary and Pancreatic Surgery Department of Liver TransplantationShulan (Hangzhou) Hospital Hangzhou Medical College Zhejiang University School of Medicine

Dear Editor, liver transplantation(lT) is the only curative therapy for patients with endstage liver disease(He et al., 2023; ling et al., 2022). Post-transplant hypertriglyceridemia(PTHT), which has an incidence of up to 32.8% in 6 months after lT, is one of the major post-transplant complications(Toshima et al., 2020).

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Irrigation-induced loess flow failure in Heifangtai Platform,North-West China

Irrigation-induced loess flow failure in Heifangtai Platform...

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中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： l.xu F.C.Dai Q.M.Gong l.G.Tham H.Min Institute of Geology and Geophysics Chinese Academy of Sciences Beijing University of Technology Department of Civil Engineering The University of Hong Kong Institute of Rock and Soil Mechanics Chinese Academy of Sciences

Because the construction of dams and hydroelectric power stations of liujiaxia and Yanguoxia across the Yellow River in West Gansu Province,North-West China,inhabitants in the reservoir areas were resettled in Heifangtai loess *** thus started in 1968. Perched water table was significantly raised and resulted in many loess flow failures in the past 30 *** type of landslide was often featured by long runout distance,high speed and *** tests along ICU and CSD stress paths were *** is shown that the loess has a strong strain-softening behavior and instability can occur in drained condition before undrained *** failure mechanism of loess flow can be interpreted as the following process:with increasing perched water table, collapse in loess was first triggered in drained condition and led to undrained loading to adjacent soil in the lower saturated part of me loess *** gravity loading applied by upper dry loess,undrained flow failure mobilized, eventually.

关键词： loess flow loess platform Agricultural irrigation laboratory test

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Continuity of Almost Harmonic Maps with the Perturbation Term in a Critical Space

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Chinese Annals of Mathematics,Series B 2022年第4期43卷 585-600页

作者： Mati ur RAHMAN Yingshu lü Deliang xu School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China

The authors study the continuity estimate of the solutions of almost harmonic maps with the perturbation term f in a critical integrability class(Zygmund class)l^(n/2)log^(q) l,n is the dimension with n≥*** prove that when q>n/2 the solution must be continuous and they can get continuity modulus *** a byproduct of their method,they also study boundary continuity for the almost harmonic maps in high dimension.

关键词： Harmonic maps Nonlinear elliptic PDE Boundary regularity

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Investigating landslide-related cracks along the edge of two loess platforms in northwest China

Investigating landslide-related cracks along the edge of two...

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中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： l.xu F.C.Dai l.G.Tham Y.F.Zhou C.X.Wu Division of Tibetan Plateau Research Institute of Geology and GeophysicsChinese Academy of Sciences Institute of Geology and Geophysics Chinese Academy of Sciences Department of Civil Engineering The University of Hong Kong

Cracks are widely developed along the edge of loess platforms in northwest *** surveys reveal that these cracks can be grouped into shallow and deeply penetrating *** former occur at a small distance from the platform edge,normally penetrate into the top unsaturated loess with the penetration depth being controlled by the joints in *** latter penetrate deeper into the saturated loess farther away from the platform *** cracks control the inflow and drainage of irrigation *** shallow penetrating crack can fail as a slide or fall with a volume of up to hundreds of cubic *** deeply penetrating crack can fail as a flow-like landslide with a volume of thousands of cubic meters or more.A full-scale field test simulating irrigation on the platform surface was *** two types of crack can be interconnected so that the water applied in the test finally flowed into the deep crack and was discharged from the *** of soil stress states and the results of field test show that the deeply-penetrating cracks could have both positive as well as negative effects on slope *** the one hand,water can flow more freely in the cracks, and the loess could be saturated and trigger a *** the other hand,the water can drain more easily along the crack and slope stability could be enhanced as the groundwater level is ***? 2012 |ohn Wiley & Sons,ltd.

关键词： cracks landslide loess plateau slope stability

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Importance of storage time in mesophilic anaerobic digestion of food waste

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Journal of Environmental Sciences 2016年第7期28卷 76-83页

作者： Fan lü Xian xu liming Shao Pinjing He State Key laboratory of Pollution Control and Resource Reuses Tongji University Institute of Waste Treatment and Reclamation Tongji University Centre for the Technology Research and Training on Household Waste in Small Towns & Rural Area Ministry of Housing and Urban–Rural Development of PR China

Storage was used as a pretreatment to enhance the methanization performance of mesophilic anaerobic digestion of food waste. Food wastes were separately stored for 0, 1,2, 3, 4, 5, 7, and 12 days, and then fed into a methanogenic reactor for a biochemical methane potential（BMP） test lasting up to 60 days. Relative to the methane production of food waste stored for 0–1 day（285–308 m l/g-added volatile solids（VSadded））, that after2–4 days and after 5–12 days of storage increased to 418–530 and 618–696 m l/g-VSadded,respectively. The efficiency of hydrolysis and acidification of pre-stored food waste in the methanization reactors increased with storage time. The characteristics of stored waste suggest that methane production was not correlated with the total hydrolysis efficiency of organics in pre-stored food waste but was positively correlated with the storage time and acidification level of the waste. From the results, we recommend 5–7 days of storage of food waste in anaerobic digestion treatment plants.

关键词： Food waste Bio-pretreatment Storage Fermentation Biochemical methane potential Hydrolysates

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