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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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De novo origination of the micropeptide controlling kernel dehydration in maize

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Science China Life Sciences 2025年

作者： Yuanliang Liu Manman Li Mingliang Xu State Key laboratory of Plant Environmental Resilience College of Agronomy and Biotechnology National Maize Improvement Center Center for Crop Functional Genomics and Molecular Breeding China Agricultural University

The mechanization of maize harvest plays a pivotal role in global food security and agricultural productivity. However, in China and many other countries, maize harvesting remains largely unmechanized, with less than ...

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Ultra‑Transparent and Multifunctional IZVO Mesh Electrodes for Next‑Generation Flexible Optoelectronics

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Nano-Micro Letters 2025年第1期17卷 293-309页

作者： Kiran A.Nirmal Tukaram D.Dongale Atul C.Khot Chenjie Yao Nahyun Kim Tae Geun Kim School of Electrical Engineering Korea UniversityAnam‑ro 145Seongbuk‑guSeoulRepublic of Korea Computational Electronics and Nanoscience Research laboratory School of Nanoscience and BiotechnologyShivaji UniversityKolhapur 416004India

Mechanically durable transparent electrodes are essential for achieving long-term stability in flexible optoelectronic ***,they are crucial for applications in the fields of energy,display,healthcare,and soft *** meshes represent a promising alternative to traditional,brittle,metal oxide conductors due to their high electrical conductivity,optical transparency,and enhanced mechanical *** this paper,we present a simple method for fabricating an ultra-transparent conducting metal oxide mesh electrode using selfcracking-assisted *** this method,we produced an electrode with ultra-transparency(97.39%),high conductance(Rs=21.24Ωsq^(−1)),elevated work function(5.16 eV),and good mechanical *** also evaluated the effectiveness of the fabricated electrodes by integrating them into organic photovoltaics,organic light-emitting diodes,and flexible transparent memristor devices for neuromorphic computing,resulting in exceptional device *** addition,the unique porous structure of the vanadium-doped indium zinc oxide mesh electrodes provided excellent flexibility,rendering them a promising option for application in flexible optoelectronics.

关键词： Self-cracking template Vanadium-doped indium zinc oxide mesh Organic solar cells Organic light-emitting diodes Flexible transparent memory

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Modifying metabolic and immune hallmarks of cancer by a copper complex

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Science China Chemistry 2025年

作者： Chengyan Chu Yunhua Zhang Chengyuan Qian Xiuzhi Yang Yicun Shang Zijian Guo Xiaoyong Wang State Key laboratory of Pharmaceutical biotechnology School of Life Sciences Nanjing University State Key laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University

Metabolic adaptation of cancer cells is a key tactic for maintaining their tumorigenicity and viability in the tumor immune microenvironment （TIME）.Concurrent modulation on the metabolic pathway and immune system could change the living condition of cancer cells and potentiate the efficacy of anticancer drugs.A copper complex （DDCu） was designed to influence the energy metabolism of cancer cells and reshape the *** restrained the production and transportation of lactate by inhibiting the expression of lactate dehydrogenase and monocarboxylate transporter 4,thereby altering the metabolic pathway of cancer cells and improving the acidic tumor ***,DDCu was reduced to Cu+by cellular glutathione to react with lipoylated proteins of the tricarboxylic acid cycle and destabilize the Fe–S cluster proteins,leading to the aggregation of dihydrolipoamide S-acetyltransferase and cuproptosis in cancer ***,DDCu promoted the polarization of macrophages from the M2 to M1 phenotype,activated CD4+and CD8+T cells,and reversed the *** a result,DDCu inhibited the tumor growth through a synergy between metabolic regulation and immunomodulation.

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Enteromorpha prolifera polysaccharide-Fe(Ⅲ) complex promotes intestinal development as a new iron supplement

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Science China Life Sciences 2025年第1期 219-231页

作者： Yingying Feng Yuying Wu Jialu Wang Zhenglin Dong Qian Yu Shuangshuang Xia Chunxue Liu Haihua Wang Xin Wu Tianjin Institute of Industrial biotechnology Chinese Academy of Sciences CAS Key laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of Sciences ANYOU biotechnology Group Co.Ltd Qingdao Seawin Biotech Group Co. LTD

Iron is a crucial micronutrient, and its deficiency can have detrimental effects on the health of infants. Dietary polysaccharide-iron(Ⅲ) complexes(PICs) are promising for addressing iron deficiency due to their minimal adverse reactions and high iron absorption rate. This study aimed to investigate the effects of dietary Enteromorpha prolifera polysaccharide-Fe(Ⅲ) complex(EP-Fe) on newborns, using 3-day weaned piglets as the iron-deficiency model. Results showed that EP-Fe improved iron levels and promoted intestinal development in piglets. Transcriptome sequencing revealed that EP-Fe increased the survival of intestinal epithelial cells under hypoxia by upregulating the expression of genes that promote the development of the vascular system. Additionally, EP-Fe enhanced the mucosal barrier functions by inhibiting myosin light chain kinase(MLCK)/phosphorylated myosin light chain(p-MLC) signaling pathway to increase the expression of intestinal tight junction proteins. Furthermore, the 16S r RNA gene sequencing of gut microbiota showed that EP-Fe promoted the enrichment of Bacteroides＿fragilis and other gut microbes that can metabolize carbohydrates. In conclusion, EP-Fe is an effective iron supplement for newborns, and it can be developed as a comprehensive nutritional supplement.

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Anti-nociceptive role of neuropeptide Y in the nucleus accumbens in rats with inflammation, an effect modulated by mu- and kappa-opioid receptors

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Progress in Natural Science:Materials International 2006年第2期16卷 133-141页

作者： LI Jinju and YU Longchuan (laboratory of Neurobiology, College of Life Sciences, and national laboratory of Biomembrane and membrane biotechnology, Peking University, Beijing 100871, China) [a]laboratory of Neurabiology College of life Sciences and National Laboratory of Biomembrane and Membrane Biotechnology Peking University Beijing China

Recent study in our laboratory showed that neuropeptide Y (NPY) plays an antinociceptive role in the nucleus accum-bens (NAc) in intact rats. The present study was performed to further investigate the effect of NPY in nociceptive modulation in the NAc of rats with inflammation, and the possible interaction between NPY and the opioid systems. Experimental inflammation was induced by subcutaneous injection of carrageenan into the left hindpaw of rats. Intra-NAc administration of NPY induced a dose-dependent increase of hindpaw withdrawal latencies (HWLs) to thermal and mechanical stimulations in rats with inflammation. The anti-nociceptive effect of NPY was significantly blocked by subsequent intra-NAc injection of the Y1 receptor antagonist NPY28-36, suggesting an involvement of Y1 receptor in the NPY-induced anti-nociception. Furthermore, intra-NAc administration of the opioid antagonist naloxone significantly antagonized the increased HWLs induced by preceding intra-NAc injection of NPY, suggesting an involvement of the endogenous opioid system in the NPY-induced anti-nociception in the NAc during inflammation. Moreover, the NPY-induced anti-nociception was attenuated by following intra-NAc injection of the μ-opioid antagonist β-funaltrexamine (β-FNA), and κ-opioid antagonist nor-binaltorphimine (nor-BNI), but not by S-opioid antagonist naltrindole, indicating that μ- and K-opioid receptors, not S-opioid receptor, are involved in the NPY-induced anti-nociception in the NAc in rats with inflammation.

关键词： nucleus accumbens, neuropeptide Y, Y1 receptor, carrageenan anti-nociception, μ- and κ-opioid receptors.

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De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期 174-180页

作者： Fan-Xiao Meng Xing-Yu Wang Ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma Bao Du Yong-Qiang Tu State Key laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

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Genistein inhibits human TNF-α-induced porcine endothelial cell adhesiveness for human monocytes and natural killer cells

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Chinese Science Bulletin 2002年第6期47卷 470-475页

作者： Xiaofeng Zhang Yan Gu Zhimin Feng Liqin Ban Meifu Feng national laboratory of Biomembrane and membrane biotechnology Institute of Zoology Chinese Academy of Sciences Beijing China

Cellular immune response is a major barrier to xenotransplantation. Human tumor necrosis factor-α (hTNF-α) possesses cross-species activity and directly amplifies the immune rejection via the upregulation of adhesion molecules on porcine endothelium. We investigated the role of protein tyrosine phosphorylation in the induction of expression of E-selectin and vascular cell adhesion molecule-1 (VCAM-1), and the augmentation of adhesion of human peripheral blood monocytes (PBMo) and natural killer cells (PBNK), after rhTNF-α-stimulation of porcine aortic endo-thelial cells (PAEC) in vitro. rhTNF-α-increased adhesiveness of PAEC for both PBMo and PBNK was dose-dependently reduced by pretreatment of PAEC with the selective protein tyrosine kinase (PTK) inhibitor genistein. The inhibitory effect occurred at the early time of PAEC activation triggered by rhTNF-α, and was completely reversible. PTK activity assay indicated that genistein also suppressed rhTNF-α stimulated activation of protein tyrosine

关键词： genistein human tumor necrosis factor-α (hTNF-α) porcine aortic endothclial cells (PAEC) human peripheral blood monocytes (PBMo) human peripheral blood natural killer cells (PBNK) cell adhesion.

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Recombinant chitinase-3-like protein 1 alleviates learning and memory impairments via M2 microglia polarization in postoperative cognitive dysfunction mice

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Neural Regeneration Research 2025年第9期20卷 2727-2736页

作者： Yujia Liu Xue Han Yan Su Yiming Zhou Minhui Xu Jiyan Xu Zhengliang Ma Xiaoping Gu Tianjiao Xia Department of Anesthesiology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina Medical School Nanjing UniversityNanjingJiangsu ProvinceChina Jiangsu Key laboratory of Molecular Medicine Nanjing UniversityNanjingJiangsu ProvinceChina State Key laboratory of Pharmaceutical biotechnology Nanjing UniversityNanjingJiangsu ProvinceChina Department of Anesthesiology Zhongshan HospitalFudan UniversityShanghaiChina

Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life of *** date,there are no viable treatment options for postoperative cognitive *** identification of postoperative cognitive dysfunction hub genes could provide new research directions and therapeutic targets for future *** identify the signaling mechanisms contributing to postoperative cognitive dysfunction,we first conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the Gene Expression Omnibus GSE95426 dataset,which consists of mRNAs and long non-coding RNAs differentially expressed in mouse hippocampus3 days after tibial *** dataset was enriched in genes associated with the biological process"regulation of immune cells,"of which Chill was identified as a hub ***,we investigated the contribution of chitinase-3-like protein 1 protein expression changes to postoperative cognitive dysfunction in the mouse model of tibial fractu re *** were intraperitoneally injected with vehicle or recombinant chitinase-3-like protein 124 hours post-surgery,and the injection groups were compared with untreated control mice for learning and memory capacities using the Y-maze and fear conditioning *** addition,protein expression levels of proinflammatory factors(interleukin-1βand inducible nitric oxide synthase),M2-type macrophage markers(CD206 and arginase-1),and cognition-related proteins(brain-derived neurotropic factor and phosphorylated NMDA receptor subunit NR2B)were measured in hippocampus by western *** with recombinant chitinase-3-like protein 1 prevented surgery-induced cognitive impairment,downregulated interleukin-1βand nducible nitric oxide synthase expression,and upregulated CD206,arginase-1,pNR2B,and brain-derived neurotropic factor expr

关键词： Chil1 hippocampus learning and memory M2 microglia neuroinflammation postoperative cognitive dysfunction(POCD) recombinant CHI3L1

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Genes and proteins expressed at different life cycle stages in the model protist Euplotes vannus revealed by both transcriptomic and proteomic approaches

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Science China Life Sciences 2025年第1期 232-248页

作者： Yaohan Jiang Xiao Chen Chundi Wang Liping Lyu Saleh A.Al-Farraj Naomi A.Stover Feng Gao Key laboratory of Evolution & Marine Biodiversity (Ministry of Education) and Institute of Evolution & Marine Biodiversity Ocean University of China Marine College Shandong University Zoology Department College of ScienceKing Saud University Department of Biology Bradley University laboratory for Marine Biology and biotechnology Qingdao Marine Science and Technology Center

Sexual reproduction first appeared in unicellular protists and has continued to be an essential biological process in almost all *** protists, which contain both germline and somatic genomes within a single cell, have evolved a special form of sexual reproduction called conjugation that involves mitosis, meiosis, fertilization, nuclear differentiation, genome rearrangement, and the development of unique cellular structures. The molecular basis and mechanisms of conjugation vary dramatically among ciliates, and many details of the process and its regulation are still largely unknown. In order to better comprehend these processes and mechanisms from an evolutionary perspective, this study provides the first comprehensive overview of the transcriptome and proteome profiles during the entire life cycle of the newly-established marine model ciliate Euplotes vannus. Transcriptome analyses from 14 life cycle stages(three vegetative stages and 11 sexual stages) revealed over 26,000 genes that are specifically expressed at different stages, many of which are related to DNA replication,transcription, translation, mitosis, meiosis, nuclear differentiation, and/or genome rearrangement. Quantitative proteomic analyses identified 338 proteins with homologs associated with conjugation and/or somatic nuclear development in other ciliates, including dicer-like proteins, Hsp90 proteins, RNA polymerase Ⅱ and transcription elongation factors, ribosomal-associated proteins, and ubiquitin-related proteins. Four of these homologs belong to the PIWI family, each with different expression patterns identified and confirmed by RT-qPCR,which may function in small RNA-mediated genome rearrangement. Proteins involved in the nonhomologous end-joining pathway are induced early during meiosis and accumulate in the developing new somatic nucleus, where more than 80% of the germline sequences are eliminated from the somatic genome. A number of new candidate genes and proteins likely t

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