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1. Integrated-Trifunctional Single Catalyst with Fine Spatial Distribution via Stepwise Anchored Strategy for Multistep Autotandem Catalysis

Author:
Ke, Shanchao; Chang, Ganggang; Hu, Zhiyi; Tian, Ge; Yang, Daiwen; Ma, Xiaochen; Huang, Kexin; Li, Jiaxin; Yang, Xiaoyu
Source:
ACS sustainable chemistry & engineering 2020 v.8 no.2 pp. 966-976
ISSN:
2168-0485
Subject:
active sites,   etc   ; catalysts; catalytic activity;     Show all 3 Subjects
Abstract:
... Tandem catalysis that facilitates a series of consecutive catalytic reactions to perform in a concurrent behavior is regarded as one of the most important future directions for enabling sustainable chemical syntheses. However, a general and facile method to finely tailor the spatial distribution of varied catalytic sites in a single catalyst to prevent chemical incompatibility while working synerg ...
DOI:
10.1021/acssuschemeng.9b05617

2. Metal-free heteroatom-doped carbon-based catalysts for ORR: A critical assessment about the role of heteroatoms

Author:
Quílez-Bermejo, Javier; Morallón, Emilia; Cazorla-Amorós, Diego
Source:
Carbon 2020 v.165 pp. 434-454
ISSN:
0008-6223
Subject:
active sites,   etc   ; carbon; catalysts; catalytic activity; electrochemistry; models; nitrogen; porosity;     Show all 8 Subjects
Abstract:
... Metal-free carbon-based catalysts have gained much attention during last years because of their interesting properties towards oxygen reduction reaction. Intrinsic parameters of carbon materials such as porosity, structural order, conductivity and defects have proved to have a strong influence in the catalytic activity of these materials. However, the highest differences in catalytic activity are ...
DOI:
10.1016/j.carbon.2020.04.068

3. Structural and functional insights about unique extremophilic bacterial lipolytic enzyme from metagenome source

Author:
Kaur, Ramanpreet; Kumar, Rajender; Verma, Swati; Kumar, Arbind; Rajesh, C.; Sharma, Pushpender Kumar
Source:
International journal of biological macromolecules 2020 v.152 pp. 593-604
ISSN:
0141-8130
Subject:
active sites,   etc   ; binding sites; calcium; enzyme activity; metagenomics; molecular dynamics;     Show all 6 Subjects
Abstract:
... In the present investigation, a lipid hydrolyzing gene RPK01 was cloned from metagenome source of hot spring. Expression and purification of recombinant protein revealed single purified protein band of ~24 KDa on 12% SDS-PAGE, and is well corroborated with the deduced molecular weight of protein as calculated from its amino acid sequence. The purified protein displayed high activity towards short ...
DOI:
10.1016/j.ijbiomac.2020.02.210

4. Selective Cl-Decoration on Nanocrystal Facets of Hematite for High-Efficiency Catalytic Oxidation of Cyclohexane: Identification of the Newly Formed Cl–O as Active Sites

Author:
Wu, Shengtao; He, Yurong; Wang, Conghui; Zhu, Chuanming; Shi, Jing; Chen, Zhaoying; Wan, Yue; Hao, Fang; Xiong, Wei; Liu, Pingle; Luo, Hean
Source:
ACS applied materials & interfaces 2020 v.12 no.23 pp. 26733-26745
ISSN:
1944-8252
Subject:
active sites,   etc   ; catalysts; catalytic activity; cyclohexanes; hematite; nanocrystals; oils; oxidation;     Show all 8 Subjects
Abstract:
... Understanding the structure–reactivity relationship at the atomic scale is of great theoretical importance for rational design of highly active catalysts, which has long been a central concern in catalysis communities and interface science. Herein, we developed a high-efficiency catalyst for catalytic oxidation of C₆H₁₂ by poststructural decoration on well-defined single-crystal facets of hematite ...
DOI:
10.1021/acsami.0c06870

5. Cryo-EM Structures of Human Drosha and DGCR8 in Complex with Primary MicroRNA

Author:
Partin, Alexander C.; Zhang, Kaiming; Jeong, Byung-Cheon; Herrell, Emily; Li, Shanshan; Chiu, Wah; Nam, Yunsun
Source:
Molecular cell 2020 v.78 no.3 pp. 411-422.e4
ISSN:
1097-2765
Subject:
active sites,   etc   ; Animalia; cryo-electron microscopy; humans; microRNA; molecular models;     Show all 6 Subjects
Abstract:
... Metazoan microRNAs require specific maturation steps initiated by Microprocessor, comprising Drosha and DGCR8. Lack of structural information for the assembled complex has hindered an understanding of how Microprocessor recognizes primary microRNA transcripts (pri-miRNAs). Here we present a cryoelectron microscopy structure of human Microprocessor with a pri-miRNA docked in the active site, poised ...
DOI:
10.1016/j.molcel.2020.02.016

6. Bioelectrofuel Synthesis by Nanoenzymes: Novel Alternatives to Conventional Enzymes

Author:
Singh, Lakhveer; Rana, Supriyanka; Thakur, Sveta; Pant, Deepak
Source:
Trends in biotechnology 2020 v.38 no.5 pp. 469-473
ISSN:
0167-7799
Subject:
active sites,   etc   ; catalysts; electrochemistry; electrodes; enzymes; microbial growth;     Show all 6 Subjects
Abstract:
... Recent bioinspired efforts of designing novel nanoenzyme-based electrocatalysts are driven by the urgency of making bioelectrofuels more affordable and efficient. Unlike natural enzymes, nanoenzyme-modified electrodes with large surface areas enclose numerous biomimicking active sites to facilitate enhanced microbial growth followed by increased reactant-to-bioelectrofuel conversion. ...
DOI:
10.1016/j.tibtech.2019.12.017

7. Nanomaterial-based gas sensors used for breath diagnosis

Author:
Zhou, Xinyuan; Xue, Zhenjie; Chen, Xiangyu; Huang, Chuanhui; Bai, Wanqiao; Lu, Zhili; Wang, Tie
Source:
Journal of materials chemistry B 2020 v.8 no.16 pp. 3231-3248
ISSN:
2050-7518
Subject:
active sites,   etc   ; biomarkers; humans; humidity; medicine; monitoring; nanomaterials; physicochemical properties;     Show all 8 Subjects
Abstract:
... Gas-sensing applications commonly use nanomaterials (NMs) because of their unique physicochemical properties, including a high surface-to-volume ratio, enormous number of active sites, controllable morphology, and potential for miniaturisation. NM-based gas sensors, as a noninvasive, real-time technique, are a promising candidate for monitoring human breath. This review focuses on NM-based gas sen ...
DOI:
10.1039/c9tb02518a

8. Silica-Modified Ordered Mesoporous Carbon for Optimized Impedance-Matching Characteristic Enabling Lightweight and Effective Microwave Absorbers

Author:
Zhou, Panpan; Zhang, Jing; Zhu, Hongli; Wang, Lixi; Wang, Xiaokang; Song, Zhi; Zhang, Qitu; Yu, Mingxun; Liu, Zhihao; Xu, Tong; Feng, Wanxun; Feng, Xia
Source:
ACS applied materials & interfaces 2020 v.12 no.20 pp. 23252-23260
ISSN:
1944-8252
Subject:
active sites,   etc   ; carbon; microwave radiation; porous media; silica; surface area;     Show all 6 Subjects
Abstract:
... Ordered mesoporous carbon (OMC) is considered to be a prospective carbon-based material for microwave absorption because of its abundant well-ordered mesoporous structures, high specific surface area, numerous active sites, and facile preparation process. However, its development has been seriously hindered by its poor impedance-matching characteristic. Herein, silica-modified OMC composites with ...
DOI:
10.1021/acsami.9b23287

9. Docking interactions determine early cleavage events in insulin proteolysis by pepsin: Experiment and simulation

Author:
Koliński, Michał; Kmiecik, Sebastian; Dec, Robert; Piejko, Marcin; Mak, Paweł; Dzwolak, Wojciech
Source:
International journal of biological macromolecules 2020 v.149 pp. 1151-1160
ISSN:
0141-8130
Subject:
active sites,   etc   ; amyloid; insulin; models; pepsin; prediction; proteolysis;     Show all 7 Subjects
Abstract:
... In silico modelling of cascade enzymatic proteolysis is an exceedingly complex and challenging task. Here, we study partial proteolysis of insulin by pepsin: a process leading to the release of a highly amyloidogenic two chain ‘H-fragment’. The H-fragment retains several cleavage sites for pepsin. However, under favorable conditions H-monomers rapidly self-assemble into proteolysis-resistant amylo ...
DOI:
10.1016/j.ijbiomac.2020.01.253

10. Induced magnetism in oxygen-decorated N-doped graphene

Author:
Romero-Muñiz, Carlos; Pou, Pablo; Pérez, Rubén
Source:
Carbon 2020 v.159 pp. 102-109
ISSN:
0008-6223
Subject:
active sites,   etc   ; adsorption; chemical reactions; graphene; magnetism; nitrogen; oxygen;     Show all 7 Subjects
Abstract:
... Covalent functionalization of two-dimensional materials is a versatile tool to induce deep changes in their initial properties leading to new functionalities. Unfortunately, in the case of graphene its poor chemical reactivity turns this task rather difficult from the practical point of view. In this work, we show how the adsorption of external species can be controlled by substitutional nitrogen ...
DOI:
10.1016/j.carbon.2019.12.007

11. Breaking Symmetry Rules Enhance the Options for Stereoselective Propene Polymerization Catalysis

Author:
De Rosa, Claudio; Di Girolamo, Rocco; Muñoz-García, Ana B.; Pavone, Michele; Talarico, Giovanni
Source:
Macromolecules 2020 v.53 no.8 pp. 2959-2964
ISSN:
1520-5835
Subject:
active sites,   etc   ; catalysts; catalytic activity; olefin; polymerization; propylene; stereoselectivity;     Show all 7 Subjects
Abstract:
... An example of breaking “Ewen’s symmetry rule” for olefin catalysis polymerization is proposed by DFT calculations. Catalyst precursors with Cₛ symmetry are suggested to promote the isotactic propene polymerization by a modification of the active site geometry obtained via coordination with AlH–alkyl species in solution. The origin of stereocontrol in olefin polymerization is due to a dual mechanis ...
DOI:
10.1021/acs.macromol.0c00280

12. Evaluation of tyrosinase inhibitory activity and mechanism of Leucrocin I and its modified peptides

Author:
Joompang, Anupong; Jangpromma, Nisachon; Choowongkomon, Kiattawee; Payoungkiattikun, Wisarut; Tankrathok, Anupong; Viyoch, Jarupa; Luangpraditkun, Kunlathida; Klaynongsruang, Sompong
Source:
Journal of bioscience and bioengineering 2020
ISSN:
1389-1723
Subject:
active sites,   etc   ; enzyme inhibition; enzymes; hyperpigmentation; melanin; peptides; toxicity;     Show all 7 Subjects
Abstract:
... This research first reports the tyrosinase inhibition and mechanism of Leucrocin I and its modified peptides (TILI-1 and TILI-2). Docking simulation showed that these peptides were predicted to bind and interact to active site of tyrosinase and exhibited the possibility to promote tyrosinase inhibition. Therefore, these peptides were synthesized, and their inhibitory activity was investigated. The ...
DOI:
10.1016/j.jbiosc.2020.04.002

13. The Influence of Cu(II) Existence State on Characteristics, Reactivity, and Recyclability of Microscale Fe/Cu Bimetal

Author:
Yuan, Yue; An, Zhengxian; Zhang, Qixian; Zhang, Yunhong; Shi, Bi; Xiong, Zhaokun; Lai, Bo
Source:
Industrial & engineering chemistry process design and development 2020 v.59 no.16 pp. 7310-7320
ISSN:
1520-5045
Subject:
active sites,   etc   ; catalytic activity; copper; copper nanoparticles; iron;     Show all 5 Subjects
Abstract:
... Despite the successes achieved in contaminant treatments with microscale Fe/Cu bimetals, some important limitations, such as high Cu loading and easily shedding of the Cu layer, cannot be ignored. The purpose of this research is to get a new mFe/Cu bimetal preparation method by changing the Cu(II) existence state during the preparation process. The Cu layer was regularly distributed on the surface ...
DOI:
10.1021/acs.iecr.0c00243

14. Assembly of cerium-based coordination polymer into variant polycrystalline 2D–3D CeO₂₋ₓ nanostructures

Author:
S. Mofarah, Sajjad; Adabifiroozjaei, Esmaeil; Wang, Yuan; Arandiyan, Hamidreza; Pardehkhorram, Raheleh; Yao, Yin; Assadi, M. Hussein N.; Mehmood, Rashid; Chen, Wen-Fan; Tsounis, Constantine; Scott, Jason; Lim, Sean; Webster, Richard; Zhong, Vicki; Xu, Yuwen; Koshy, Pramod; Sorrell, Charles C.
Source:
Journal of materials chemistry A 2020 v.8 no.9 pp. 4753-4763
ISSN:
2050-7496
Subject:
active sites,   etc   ; coordination polymers; cost effectiveness; nanosheets; photocatalysis; solar radiation;     Show all 6 Subjects
Abstract:
... Precise control over the morphology of nanomaterials is critical yet challenging. The present work reports an efficient approach to tailor the architecture of nanostructures. The process involves rapid disassembly/reassembly of an unstable metal-based coordination polymer (MCP) by controlling the kinetics of the reassembly process. The synthesis procedure delivers unprecedented polycrystalline nan ...
DOI:
10.1039/c9ta11961b

15. Engineering effective structural defects of metal–organic frameworks to enhance their catalytic performances

Author:
Wang, Jianjian; Liu, Lingmei; Chen, Cailing; Dong, Xinglong; Wang, Qin; Alfilfil, Lujain; AlAlouni, Mohammed R.; Yao, Kexin; Huang, Jianfeng; Zhang, Daliang; Han, Yu
Source:
Journal of materials chemistry A 2020 v.8 no.8 pp. 4464-4472
ISSN:
2050-7496
Subject:
active sites,   etc   ; catalytic activity; coordination polymers; cyclohexanones; engineering; hydrogen;     Show all 6 Subjects
Abstract:
... Metal–organic frameworks (MOFs) with a high density of metal nodes have great potential in the application of heterogeneous catalysis. However, identifying the real active site in MOF structures and tuning its amount to further improve its catalytic performance are still a great challenge. In this paper, defective UiO-66 modulated with trifluoroacetic acid (TFA) was synthesized and used for the co ...
DOI:
10.1039/c9ta12230c

16. Structural and Functional Analysis of Ubiquitin-based Inhibitors That Target the Backsides of E2 Enzymes

Author:
Garg, Pankaj; Ceccarelli, Derek F.; Keszei, Alexander F.A.; Kurinov, Igor; Sicheri, Frank; Sidhu, Sachdev S.
Source:
Journal of molecular biology 2020 v.432 no.4 pp. 952-966
ISSN:
0022-2836
Subject:
active sites,   etc   ; crystal structure; cysteine; neoplasms; phages; screening; ubiquitin; ubiquitination;     Show all 8 Subjects
Abstract:
... Ubiquitin-conjugating E2 enzymes are central to the ubiquitination cascade and have been implicated in cancer and other diseases. Despite strong interest in developing specific E2 inhibitors, the shallow and exposed active site has proven recalcitrant to targeting with reversible small-molecule inhibitors. Here, we used phage display to generate highly potent and selective ubiquitin variants (UbVs ...
DOI:
10.1016/j.jmb.2019.09.024
PubMed:
31634471
PubMed Central:
PMC7054140

17. Insights into high capacity and ultrastable carbonaceous anodes for potassium-ion storage via a hierarchical heterostructure

Author:
Ma, Chunrong; Yang, Huijun; Xu, Zhixin; Fu, Zhengguang; Xie, Yingying; Zhang, Hongti; Hong, Min; Ma, ZiFeng; Xiong, Hui; Yuan, Xian-Zheng
Source:
Journal of materials chemistry A 2020 v.8 no.5 pp. 2836-2842
ISSN:
2050-7496
Subject:
active sites,   etc   ; adsorption; anodes; batteries; carbon; ions; porous media; potassium;     Show all 8 Subjects
Abstract:
... Carbonaceous materials are promising anode materials for potassium-ion batteries (PIBs). However, due to the large size of K⁺ ions, pristine carbon anode materials exhibit poor rate capability and unsatisfactory cycling stability. Herein, a novel anode with a hierarchical porous carbon structure and defects is reported. Integrating the mesoporous structure and P-dopants at the carbon surface not o ...
DOI:
10.1039/c9ta12997a

18. Rational design of stable sulfur vacancies in molybdenum disulfide for hydrogen evolution

Author:
Zhao, Yunxing; Tang, Michael T.; Wu, Sudong; Geng, Jing; Han, Zhaojun; Chan, Karen; Gao, Pingqi; Li, Hong
Source:
Journal of catalysis 2020 v.382 pp. 320-328
ISSN:
0021-9517
Subject:
active sites,   etc   ; catalysts; graphene; hydrogen production; molybdenum disulfide; sulfur;     Show all 6 Subjects
Abstract:
... Sulfur (S) vacancies in MoS₂ have been found to act as a new active center, which shows an unprecedented intrinsic HER activity under elastic strain. However, such S-vacancies are unstable and the activities are very sensitive to the vacancy concentration. A strategy to stabilize these abundant active sites is thus highly desirable. Herein, we rationally design a catalyst system to stabilize S-vac ...
DOI:
10.1016/j.jcat.2019.12.028

19. Enhancement of CeO₂ Silanization by Spontaneous Breakage of Si–O Bonds through Facet Engineering

Author:
Ma, Hongyang; Ren, Hangjuan; Koshy, Pramod; Sorrell, Charles C.; Hart, Judy N.
Source:
Journal of physical chemistry 2020 v.124 no.4 pp. 2644-2655
ISSN:
1932-7455
Subject:
active sites,   etc   ; adsorption; ceric oxide; chemical bonding; engineering; nanoparticles;     Show all 6 Subjects
Abstract:
... Facet engineering is a new method of materials design with considerable potential for many technological applications. The present work uses DFT calculations to understand how this strategy can be used to accelerate the silanization of tetraethyl orthosilicate (TEOS) on the surface of ceria (CeO₂), which is a key technology in biomedical and other fields. Cubic CeO₂ nanoparticles with exposed {100 ...
DOI:
10.1021/acs.jpcc.9b08406

20. Local Aromaticity: An Important Indicator of the Surface Active Sites of Heterocyclic Nanostructures

Author:
Wei, Zhan; Yang, Le; Hao, Debo; Liu, Chang; Hou, Qinghua; Li, Lanlan; Jin, Peng
Source:
Journal of physical chemistry 2020 v.124 no.4 pp. 2583-2590
ISSN:
1932-7455
Subject:
active sites,   etc   ; adsorption; catalytic activity; fullerene; heterocyclic compounds; nanosheets; nanotubes;     Show all 7 Subjects
Abstract:
... Quick identification of the active sites on the surfaces of nanomaterials is rather critical for disclosing their exact interaction mechanism with various adsorbates in the general adsorption and catalysis processes. In this work, we propose that the local aromaticity of the surface sites (bonds or atoms) of different heterocyclic nanostructures (fullerenes, nanotubes, and nanosheets) could be eas ...
DOI:
10.1021/acs.jpcc.0c00071