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排序方式: 共有525条查询结果,搜索用时 516 毫秒
521.
Fei Cao Lie-Feng Ma Long-Shuang Hu Chu-Xuan Xu Xuepeng Chen Zha-Jun Zhan Prof. Qing-Wei Zhao Prof. Xu-Ming Mao 《Angewandte Chemie (International ed. in English)》2023,62(5):e202214814
Efficient biosynthesis of microbial bioactive natural products (NPs) is beneficial for the survival of producers, while self-protection is necessary to avoid self-harm resulting from over-accumulation of NPs. The underlying mechanisms for the effective but tolerable production of bioactive NPs are not well understood. Herein, in the biosynthesis of two fungal polyketide mycotoxins aurovertin E ( 1 ) and asteltoxin, we show that the cyclases in the gene clusters promote the release of the polyketide backbone, and reveal that a signal peptide is crucial for their subcellular localization and full activity. Meanwhile, the fungus adopts enzymatic acetylation as the major detoxification pathway of 1 . If intermediates are over-produced, the non-enzymatic shunt pathways work as salvage pathways to avoid excessive accumulation of the toxic metabolites for self-protection. These findings provided new insight into the interplay of efficient backbone release and multiple detoxification strategies for the production of fungal bioactive NPs. 相似文献
522.
Han-Bin Xu Dr. Hua-Ying Chen Dr. Jian Lv Dr. Bin-Bin Chen Ze-Rui Zhou Shuai Chang Ya-Ting Gao Wen-Fei Huang Ming-Jie Ye Zi-Jian Cheng Dr. Mahmoud Elsayed Hafez Prof. Ruo-Can Qian Prof. Da-Wei Li 《Angewandte Chemie (International ed. in English)》2023,62(44):e202311002
Artificially performing chemical reactions in living biosystems to attain various physiological aims remains an intriguing but very challenging task. In this study, the Schiff base reaction was conducted in cells using Sc(OTf)3 as a catalyst, enabling the in situ synthesis of a hollow covalent organic polymer (HCOP) without external stimuli. The reversible Schiff base reaction mediated intracellular Oswald ripening endows the HCOP with a spherical, hollow porous structure and a large specific surface area. The intracellularly generated HCOP reduced cellular motility by restraining actin polymerization, which consequently induced mitochondrial deactivation, apoptosis, and necroptosis. The presented intracellular synthesis system inspired by the Schiff base reaction has strong potential to regulate cell fate and biological functions, opening up a new strategic possibility for intervening in cellular behavior. 相似文献
523.
Jing-Yu Li Chang-Long Tan Ming-Yu Qi Prof. Dr. Zi-Rong Tang Prof. Dr. Yi-Jun Xu 《Angewandte Chemie (International ed. in English)》2023,62(22):e202303054
Photocatalytic epoxide alcoholysis through C−O bond cleavage and formation has emerged as an alternative to synthesizing anti-tumoral pharmaceuticals and fine chemicals. However, the lack of crucial evidence to interpret the interaction between reactants and photocatalyst surface makes it challenging for photocatalytic epoxide alcoholysis with both high activity and regioselectivity. In this work, we report the hierarchical ZnIn2S4@CdS photocatalyst for epoxide alcoholysis with high regioselectivity nearly 100 %. Mechanistic studies unveil that the precise activation switch on exposed Zn acid sites for C−O bond polarization and cleavage has a critical significance for achieving efficient photocatalytic performance. Furthermore, the establishment of Z-scheme heterojunction facilitates the interface charge separation and transfer. Remarkably, the underlying regioselective photocatalytic reaction pathway has been distinctly revealed. 相似文献
524.
Many scholars have argued that anonymity is the main factor in opinion polarization. In recent studies, scholars have found that being with like-minded others can lead people to adopt extreme opinions. The aim of the current study was to explore how these two online environmental factors impact people to move their opinions toward an extreme position (polarize). In addition to environmental factors, we investigated how an individual trait (i.e., need for approval) influenced people to take pre-existing opinions to an extreme position (polarize). We conducted an online experiment (2 [anonymity vs non-anonymity] by 2 [like-minded others vs different-minded others]) using Amazon Mechanical Turk workers (n = 476). Findings showed that being with like-minded others led individuals to move their opinions toward extremity. Furthermore, we found that among participants who were with like-minded others, those in the anonymous condition were most likely to move their opinions toward an extreme end. However, the need for approval did not play a significant moderating role in this process. 相似文献
525.
Kyungsene Lee Brandon Davis Xuelin Wang Shubham Mirg Connie Wen Dr. Lidya Abune Dr. Benjamin E. Peterson Dr. Li Han Haoyang Chen Prof. Hongjun Wang Prof. Spencer E. Szczesny Prof. Yuguo Lei Prof. Sri-Rajasekhar Kothapalli Prof. Yong Wang 《Angewandte Chemie (International ed. in English)》2023,62(31):e202306583
Cell encapsulation has been studied for various applications ranging from cell transplantation to biological production. However, current encapsulation technologies focus on cell protection rather than cell regulation that is essential to most if not all cell-based applications. Here we report a method for cell nanoencapsulation and regulation using an ultrathin biomimetic extracellular matrix as a cell nanocapsule to carry nanoparticles (CN2). This method allows high-capacity nanoparticle retention at the vicinity of cell surfaces. The encapsulated cells maintain high viability and normal metabolism. When gold nanoparticles (AuNPs) are used as a model to decorate the nanocapsule, light irradiation transiently increases the temperature, leading to the activation of the heat shock protein 70 (HSP70) promoter and the regulation of reporter gene expression. As the biomimetic nanocapsule can be decorated with any or multiple NPs, CN2 is a promising platform for advancing cell-based applications. 相似文献