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991.
Rongying Liu Dr. Zdravko Kochovski Long Li Yue-wen Yin Jing Yang Guang Yang Guoqing Tao Anqiu Xu Ensong Zhang Prof. Dr. Hong-ming Ding Prof. Dr. Yan Lu Prof. Dr. Guosong Chen Prof. Dr. Ming Jiang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9704-9710
A protein Pascal triangle has been constructed as new type of supramolecular architecture by using the inducing ligand strategy that we previously developed for protein assemblies. Although mathematical studies on this famous geometry have a long history, no work on such Pascal triangles fabricated from native proteins has been reported so far due to their structural complexity. In this work, by carefully tuning the specific interactions between the native protein building block WGA and the inducing ligand R-SL , a 2D Pascal-triangle lattice with three types of triangular voids has been assembled. Moreover, a 3D crystal structure was obtained based on the 2D Pascal triangles. The distinctive carbohydrate binding sites of WGA and the intralayer as well as interlayer dimerization of RhB was the key to facilitate nanofabrication in solution. This strategy may be applied to prepare and explore various sophisticated assemblies based on native proteins. 相似文献
992.
Qiangzhe Zhang Dr. Ronnie H. Fang Dr. Weiwei Gao Dr. Liangfang Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(26):10547-10551
Inhibition of phospholipase A2 (PLA2) has long been considered for treating various diseases associated with an elevated PLA2 activity. However, safe and effective PLA2 inhibitors remain unavailable. Herein, we report a biomimetic nanoparticle design that enables a “lure and kill” mechanism designed for PLA2 inhibition (denoted “L&K-NP”). The L&K-NPs are made of polymeric cores wrapped with modified red blood cell membrane with two inserted key components: melittin and oleyloxyethyl phosphorylcholine (OOPC). Melittin acts as a PLA2 attractant that works together with the membrane lipids to “lure” in-coming PLA2 for attack. Meanwhile, OOPC acts as inhibitor that “kills” PLA2 upon enzymatic attack. Both compounds are integrated into the L&K-NP structure, which voids toxicity associated with free molecules. In the study, L&K-NPs effectively inhibit PLA2-induced hemolysis. In mice administered with a lethal dose of venomous PLA2, L&K-NPs also inhibit hemolysis and confer a significant survival benefit. Furthermore, L&K-NPs show no obvious toxicity in mice. and the design provides a platform technology for a safe and effective anti-PLA2 approach. 相似文献
993.
Dr. Xiangyuan Ouyang Meifang Wang Linjie Guo Chengjun Cui Ting Liu Yongan Ren Yan Zhao Dr. Zhilei Ge Xiniu Guo Prof. Gang Xie Dr. Jiang Li Prof. Chunhai Fan Prof. Lihua Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(29):11934-11942
Fluorescent copper nanoclusters (CuNCs) have been widely used in chemical sensors, biological imaging, and light-emitting devices. However, individual fluorescent CuNCs have limitations in their capabilities arising from poor photostability and weak emission intensities. As one kind of aggregation-induced emission luminogen (AIEgen), the formation of aggregates with high compactness and good order can efficiently improve the emission intensity, stability, and tunability of CuNCs. Here, DNA nanoribbons, containing multiple specific binding sites, serve as a template for in situ synthesis and assembly of ultrasmall CuNCs (0.6 nm). These CuNC self-assemblies exhibit enhanced luminescence and excellent fluorescence stability because of tight and ordered arrangement through DNA nanoribbons templating. Furthermore, the stable and bright CuNC assemblies are demonstrated in the high-sensitivity detection and intracellular fluorescence imaging of biothiols. 相似文献
994.
Tao Ding Liyuan Zhu Yuxin Fang Yangluorong Liu Wei Tang Prof. Dr. Peng Zou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(51):23133-23137
The spatial arrangement of chromosome within the nucleus is linked to genome function and gene expression regulation. Existing genome-wide mapping methods often rely on chemically crosslinking DNA with protein baits, which raises concerns of artifacts being introduced during cell fixation. By genetically targeting a photosensitizer protein to specific subnuclear locations, we achieved blue-light-activated labeling of local DNA with a bioorthogonal functional handle for affinity purification and sequence identification through next-generation sequencing. When applied to the nuclear lamina in human embryonic kidney 293T cells, it revealed lamina-associated domains (LADs) that cover 37.6 % of the genome. These LADs overlap with heterochromatin hallmarks and are depleted with CpG islands. This simple labeling method avoids the harsh treatment of chemical crosslinking and is generally applicable to the genome-wide high-resolution mapping of the spatial chromosome organization in living cells. 相似文献
995.
Yajie Liu Zelin Duan Jing Fang Fan Zhang Prof. Junyu Xiao Prof. Wen-Bin Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16256-16261
Herein, we report the biosynthesis of protein heterocatenanes using a programmed sequence of multiple post-translational processing events including intramolecular chain entanglement, in situ backbone cleavage, and spontaneous cyclization. The approach is general, autonomous, and can obviate the need for any additional enzymes. The catenane topology was convincingly proven using a combination of SDS-PAGE, LC-MS, size exclusion chromatography, controlled proteolytic digestion, and protein crystallography. The X-ray crystal structure clearly shows two mechanically interlocked protein rings with intact folded domains. It opens new avenues in the nascent field of protein-topology engineering. 相似文献
996.
Dr. Pu Bai Dr. Zhuoya Dong Dr. Shuang Wang Dr. Xiangyu Wang Dr. Yue Li Dr. Yunzheng Wang Prof. Dr. Yanhang Ma Prof. Dr. Wenfu Yan Prof. Dr. Xiaodong Zou Prof. Dr. Jihong Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(44):19707-19712
Cationic framework materials, especially pure inorganic cationic frameworks that can efficiently and selectively capture harmful heavy metal oxyanions from aqueous solution are highly desired yet scarcely reported. Herein, we report the discovery of a 2D cationic aluminum oxyhydroxide, JU-111, which sets a new benchmark for heavy metal oxyanion sorbents, especially for CrVI. Its structure was solved based on 3D electron diffraction tomography data. JU-111 shows fast sorption kinetics (ca. 20 min), high capture capacity (105.4 mg g−1), and broad working pH range (3–10) toward CrVI oxyanions. Unlike layered double hydroxides (LDHs), which are poorly selective in the presence of CO32−, JU-111 retains excellent selectivity for CrVI even under a large excess of CO32−. These superior features coupled with the ultra-low cost and environmentally benign nature make JU-111 a promising candidate for toxic metal oxyanion remediation as well as other potential applications. 相似文献
997.
Diandian Shi Dr. Kok-Giap Haw Dr. Cassandre Kouvatas Lingxue Tang Yiying Zhang Prof. Dr. Qianrong Fang Prof. Dr. Shilun Qiu Prof. Dr. Valentin Valtchev 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(44):19744-19749
Aluminosilicate zeolites are synthesized under hydrothermal conditions in a basic/alkaline medium in the pH range between 9 and 14. The synthesis of MFI-type zeolite in an acidic medium is presented. The critical parameter determining the zeolite formation in an acidic medium was found to be the isoelectric point (IEP) of gel particles. MFI-type zeolite was synthesized above the isoelectric point of the employed silica source, where the silica species exhibit a negative charge and the paradigm of zeolite formation based on the electrostatic interaction with the positively charged template is retained. No zeolite formation is observed below the isoelectric point of silica. The impact of aluminum on the zeolite formation is also studied. The results of this study will serve to extend the synthesis field of high silica zeolites to the acidic medium and thus open new opportunities to control the zeolite properties. 相似文献
998.
Dr. Deng Pan Zhengzou Fang Erli Yang Zhenqiang Ning Qing Zhou Kaiyang Chen Yongjun Zheng Prof. Yuanjian Zhang Prof. Yanfei Shen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(38):16890-16897
The exceptional nature of WO3−x dots has inspired widespread interest, but it is still a significant challenge to synthesize high-quality WO3−x dots without using unstable reactants, expensive equipment, and complex synthetic processes. Herein, the synthesis of ligand-free WO3−x dots is reported that are highly dispersible and rich in oxygen vacancies by a simple but straightforward exfoliation of bulk WS2 and a mild follow-up chemical conversion. Surprisingly, the WO3−x dots emerged as co-reactants for the electrochemiluminescence (ECL) of Ru(bpy)32+ with a comparable ECL efficiency to the well-known Ru(bpy)32+/tripropylamine (TPrA) system. Moreover, compared to TPrA, whose toxicity remains a critical issue of concern, the WO3−x dots were ca. 300-fold less toxic. The potency of WO3−x dots was further explored in the detection of circulating tumor cells (CTCs) with the most competitive limit of detection so far. 相似文献
999.
Dr. Song Jin Youxuan Ni Zhimeng Hao Prof. Kai Zhang Dr. Yong Lu Dr. Zhenhua Yan Dr. Yajuan Wei Dr. Ying-Rui Lu Dr. Ting-Shan Chan Prof. Jun Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22069-22073
A general graphene quantum dot-tethering design strategy to synthesize single-atom catalysts (SACs) is presented. The strategy is applicable to different metals (Cr, Mn, Fe, Co, Ni, Cu, and Zn) and supports (0D carbon nanosphere, 1D carbon nanotube, 2D graphene nanosheet, and 3D graphite foam) with the metal loading of 3.0–4.5 wt %. The direct transmission electron microscopy imaging and X-ray absorption spectra analyses confirm the atomic dispersed metal in carbon supports. Our study reveals that the abundant oxygenated groups for complexing metal ions and the rich defective sites for incorporating nitrogen are essential to realize the synthesis of SACs. Furthermore, the carbon nanotube supported Ni SACs exhibits high electrocatalytic activity for CO2 reduction with nearly 100 % CO selectivity. This universal strategy is expected to open up new research avenues to produce SACs for diverse electrocatalytic applications. 相似文献
1000.
Guangjun Li Weigang Hu Yongnan Sun Jiayu Xu Xiao Cai Xinglian Cheng Yuying Zhang Ancheng Tang Xu Liu Prof. Mingyang Chen Prof. Weiping Ding Prof. Yan Zhu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(47):21321-21328
The emergence of atomically precise metal nanoclusters with unique electronic structures provides access to currently inaccessible catalytic challenges at the single-electron level. We investigate the catalytic behavior of gold Au25(SR)18 nanoclusters by monitoring an incoming and outgoing free valence electron of Au 6s1. Distinct performances are revealed: Au25(SR)18− is generated upon donation of an electron to neutral Au25(SR)180 and this is associated with a loss in reactivity, whereas Au25(SR)18+ is generated from dislodgment of an electron from neutral Au25(SR)180 with a loss in stability. The reactivity diversity of the three Au25(SR)18 clusters stems from different affinities with reactants and the extent of intramolecular charge migration during the reactions, which are closely associated with the valence occupancies of the clusters varied by one electron. The stability difference in the three clusters is attributed to their different equilibria, which are established between the AuSR dissociation and polymerization influenced by one electron. 相似文献