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991.
Discovery of the Tiancilactone Antibiotics by Genome Mining of Atypical Bacterial Type II Diterpene Synthases 下载免费PDF全文
Dr. Liao‐Bin Dong Dr. Jeffrey D. Rudolf Dr. Ming‐Rong Deng Dr. Xiaohui Yan Prof. Dr. Ben Shen 《Chembiochem : a European journal of chemical biology》2018,19(16):1727-1733
Although genome mining has advanced the identification, discovery, and study of microbial natural products, the discovery of bacterial diterpenoids continues to lag behind. Herein, we report the identification of 66 putative producers of novel bacterial diterpenoids, and the discovery of the tiancilactone (TNL) family of antibiotics, by genome mining of type II diterpene synthases that do not possess the canonical DXDD motif. The TNLs, which are broad‐spectrum antibiotics with moderate activities, are produced by both Streptomyces sp. CB03234 and Streptomyces sp. CB03238 and feature a highly functionalized diterpenoid skeleton that is further decorated with chloroanthranilate and γ‐butyrolactone moieties. Genetic manipulation of the tnl gene cluster resulted in TNL congeners, which provided insights into their biosynthesis and structure–activity relationships. This work highlights the biosynthetic potential that bacteria possess to produce diterpenoids and should inspire continued efforts to discover terpenoid natural products from bacteria. 相似文献
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Xin Yang Wenzhuo Deng Ming Chen Yaobing Wang Chuan-Fu Sun 《Advanced materials (Deerfield Beach, Fla.)》2020,32(45):2003592
Low-cost and high-safety aqueous Zn-ion batteries are an exceptionally compelling technology for grid-scale energy storage. However, their development has been plagued by the lack of stable cathode materials allowing fast Zn2+-ion insertion and scalable synthesis. Here, a lattice-water-rich, inorganic-open-framework (IOF) phosphovanadate cathode, which is mass-producible and delivers high capacity (228 mAh g−1) and energy density (193.8 Wh kg−1 or 513 Wh L−1), is reported. The abundant lattice waters functioning as a “charge shield” enable a low Zn2+-migration energy barrier, (0.66 eV) even close to that of Li+ within LiFePO4. This fast intrinsic ion-diffusion kinetics, together with nanostructure effect, allow the achievements of ultrafast charging (71% state of charge in 1.9 min) and an ultrahigh power density (7200 W kg−1 at 107 Wh kg−1). Equally important, the IOF exhibits a quasi-zero-strain feature (<1% lattice change upon (de)zincation), which ensures ultrahigh cycling durability (3000 cycles) and Coulombic efficiencies of 100%. The cell-level energy and power densities reach ≈90 Wh kg−1 and ≈3320 W kg−1, far surpassing commercial lead–acid, Ni–Cd, and Ni–MH batteries. Lattice-water-rich IOFs may open up new opportunities for exploring stable and fast-charging Zn-ion batteries. 相似文献
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High-efficiency multipartite entanglement purification of electron-spin states with charge detection
Tao Li Bao-Cang Ren Hai-Rui Wei Ming Hua Fu-Guo Deng 《Quantum Information Processing》2013,12(2):855-876
We present a high-efficiency multipartite entanglement purification protocol (MEPP) for electron-spin systems in a Greenberger–Horne–Zeilinger state based on their spins and their charges. Our MEPP contains two parts. The first part is our normal MEPP with which the parties can obtain a high-fidelity N-electron ensemble directly, similar to the MEPP with controlled-not gates. The second one is our recycling MEPP with entanglement link from N′-electron subsystems (2 < N′ < N). It is interesting to show that the N′-electron subsystems can be obtained efficiently by measuring the electrons with potential bit-flip errors from the instances which are useless and are just discarded in all existing conventional MEPPs. Combining these two parts, our MEPP has the advantage of the efficiency higher than other MEPPs largely for electron-spin systems. 相似文献
999.
介绍了近几年来不同形貌SBA-15材料的设计组装过程,叙述了在非离子嵌段共聚物模板剂下,陈化温度、搅拌速率、共表面活性剂和无机盐等因素对SBA-15介孔材料形貌的影响,及其合成机理。介绍了不同形貌SBA-15材料的应用现状。认为不同形貌的SBA-15介孔材料对催化、吸附分离等反应具有不同的影响,但是对于每一种反应,总有一种形貌的SBA-15的反应性能是最佳的;为使机械性能和水热稳定性能优良的具有二维六方介孔结构的SBA-15材料能更好地应用于各领域,继续研究不同形貌的SBA-15的设计组装过程对催化、吸附分离和燃料电池等领域具有深远的意义。 相似文献
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Jinyan Deng Qian Xiu Lihui Guo Lirong Zhang Gaojun Wen Chaofan Zhong 《Journal of Materials Science》2012,47(7):3383-3390
Four donor–π–acceptor type polymeric metal complexes (PCo–F, PCo–B, PNi–F, and PNi–B) with Co(II) or Ni(II) complexes in the
branched chain were synthesized by the Heck coupling and utilized as dyes for dye-sensitized solar cells (DSSCs). The structures,
photophysical, electrochemicals, and thermal properties of the four dyes were investigated in detail, and the results showed
that dye containing Ni(II) complex and alkoxy benzene unit benefited the generation of photocurrent and the open-circuit voltages.
The polymeric metal complexes possess good thermal stability and exhibit good solubility in common organic solvents such as
chloroform, THF, and toluene. The maximal power conversion efficiency of 1.21% (J
sc = 2.49 mA/cm2, V
oc = 0.695 V, FF = 0.59) was obtained with a DSSCs based on PNi–B dye under simulated air mass 1.5 G solar irradiation. 相似文献