bluuebunny/crossref_metadata_2025_split huggingface dataset:
DNA Framework‐Based Topological Cell Sorters
Authors: Yin Fangfei , Li Min , Mao Xiuhai , Li Fan , Xiang Xuelin , Li Qian , Wang Lihua , Zuo Xiaolei , Fan Chunhai , Zhu Ying 
Published: March 2020

AbstractMolecular recognition in cell biological process is characterized with specific locks‐and‐keys interactions between ligands and receptors, which are ubiquitously distributed on cell membrane with topological clustering. Few topologically‐engineered ligand systems enable the exploration of the binding strength between ligand‐receptor topological organization. Herein, we generate topologically controlled ligands by developing a family of tetrahedral DNA frameworks (TDFs), so the multiple ligands are stoichiometrically and topologically arranged. This topological control of multiple ligands changes the nature of the molecular recognition by inducing the receptor clustering, so the binding strength is significantly improved (ca. 10‐fold). The precise engineering of topological complexes formed by the TDFs are readily translated into effective binding control for cell patterning and binding strength control of cells for cell sorting. This work paves the way for the development of versatile design of topological ligands.
Regioselective Insertion of Aluminum(I) in the cyclo‐P5 Ring of Pentaphosphaferrocene
Authors: Yadav Ravi , Simler Thomas , Goswami Bhupendra , Schoo Christoph , Köppe Ralf , Dey Subhayan , Roesky Peter W. 
Published: March 2020

AbstractA route to directly access mixed Al–Fe polyphosphide complexes was developed. The reactivity of pentaphosphaferrocene, [Cp*Fe(η5‐P5)] (Cp*=C5Me5), with two different low‐valent aluminum compounds was investigated. The steric and electronic environment around the [AlI] centre are found to be crucial for the formation of the resulting Al–Fe polyphosphides. Reaction with the sterically demanding [Dipp‐BDIAlI] (Dipp‐BDI={[2,6‐iPr2C6H3NCMe]2CH}−) resulted in the first Al‐based neutral triple‐decker type polyphosphide complex. For [(Cp*AlI)4], an unprecedented regioselective insertion of three [Cp*AlIII]2+ moieties into two adjacent P−P bonds of the cyclo‐P5 ring of [Cp*Fe(η5‐P5)] was observed. The regioselectivity of the insertion reaction could be rationalized by isolating an analogue of the reaction intermediate stabilized by a strong σ‐donor carbene.
Evolved, Selective Erasers of Distinct Lysine Acylations
Authors: Spinck Martin , Neumann‐Staubitz Petra , Ecke Maria , Gasper Raphael , Neumann Heinz 
Published: March 2020

AbstractLysine acylations, a family of diverse protein modifications varying in acyl‐group length, charge, and saturation, are linked to many important physiological processes. Only a small set of substrate‐promiscuous lysine acetyltransferases and deacetylases (KDACs) install and remove this vast variety of modifications. Engineered KDACs that remove only one type of acylation would help to dissect the different contributions of distinct acylations. We developed a bacterial selection system for the directed evolution of KDACs and identified variants up to 400 times more selective for butyryl‐lysine compared to crotonyl‐lysine. Structural analyses revealed that the enzyme adopts different conformational states depending on the type of acylation of the bound peptide. We used the butyryl‐selective KDAC variant to shift the cellular acylation spectrum towards increased lysine crotonylation. These new enzymes will help in dissecting the roles of different lysine acylations in cell physiology.
Mechanically Robust and Broadband Blackbody Composite Films Based on Self‐Assembled Layered Structures
Authors: Yan Jun , Wu Mengjiao , Han Yi , Chen Yulan , Liu Mingjie 
Published: March 2020

AbstractInspired by nacre that is mechanically strong and versatile in light manipulation, large‐scale black films with a nacre‐like microstructure and carbon nanotube inclusion were prepared using a facile self‐assembly technique. A layered structure promoting blackness and toughness simultaneously was realized, affording robust films with a solar–absorptivity as high as 96.9%. Our design strategy and fabrication process will be beneficial for the facile access to various advanced blackbody coatings.
Ebenensystem zur Resilienzbewertung kritischer Verkehrsinfrastrukturen am Beispiel der Wasserstraßen
Authors: Wehrle Rebecca , Wiens Marcus , Schultmann Frank , Akkermann Jan , Bödefeld Jörg 
Published: March 2020

AbstractVerkehrsinfrastrukturen sind elementarer Bestandteil der heutigen global vernetzten Welt. Dennoch werden diese wichtigen Infrastrukturen in vielen Ländern zunehmend strukturell anfälliger, weil sie oft von Überalterung und einem zunehmenden Instandhaltungsrückstau geprägt sind. Insbesondere im Bereich der Wasserstraßen sind zudem die Kenntnisse über die Anfälligkeit der Bauwerke und das Gefahrenpotenzial bei Versagen oder aktiver Zerstörung lückenhaft oder veraltet. Es besteht akuter Handlungsbedarf hinsichtlich einer Steigerung der Resilienz einzelner Bauwerke und somit des gesamten Systems Wasserstraße als kritische Verkehrsinfrastruktur. Hierzu wird im Rahmen der Sicherheitsforschung der Bundesrepublik Deutschland ein systemischer Ansatz entwickelt, der die Ableitung einer risikobasierten Instandhaltungsstrategie ermöglicht. Risikoanalysen bewerten die Vulnerabilität unterschiedlicher Bauwerkstypen und identifizieren gefährdete Verkehrswasserbauwerke anhand der Bewertung der Versagensfolgen. Die Versagensfolgen reichen dabei von Funktionsausfällen einzelner Bauwerke über wirtschaftliche Schäden durch sinkende Transportleistungen im Güterverkehr bis hin zu Gefährdungen für die Bevölkerung, die mit dem Versagen der Wasserstraßeninfrastruktur einhergehen.
GTP hydrolysis is modulated by Arg34 in the RASopathy‐associated KRASP34R
Authors: Bera Asim K. , Lu Jia , Lu Chunya , Li Lianbo , Gondi Sudershan , Yan Wei , Nelson Andrew , Zhang Goujun , Westover Kenneth D. 
Published: March 2020

AbstractRAS proteins are commonly mutated in cancerous tumors, but germline RAS mutations are also found in RASopathy syndromes such as Noonan syndrome (NS) and cardiofaciocutaneous (CFC) syndrome. Activating RAS mutations can be subclassified based on their activating mechanisms. Understanding the structural basis for these mechanisms may provide clues for how to manage associated health conditions. We determined high‐resolution X‐ray structures of the RASopathy mutant KRASP34R seen in NS and CFCS. GTP and GDP‐bound KRASP34R crystallized in multiple forms, with each lattice consisting of multiple protein conformations. In all GTP‐bound conformations, the switch regions are not compatible with GAP binding, suggesting a structural mechanism for the GAP insensitivity of this RAS mutant. However, GTP‐bound conformations are compatible with intrinsic nucleotide hydrolysis, including one that places R34 in a position analogous to the GAP arginine finger or intrinsic arginine finger found in heterotrimeric G proteins, which may support intrinsic GTP hydrolysis. We also note that the affinity between KRASP34R and RAF‐RBD is decreased, suggesting another possible mechanism for dampening of RAS signaling. These results may provide a foothold for development of new mutation‐specific strategies to address KRASP34R‐driven diseases.
Preparation, statistical optimization and characterization of poly(3‐hydroxybutyrate) fermented by Cupriavidus necator utilizing various hydrolysates of alligator weed (Alternanthera philoxeroides) as a sole carbon source
Authors: Zhang Youwei , Li Tingting , Shen Yingbin , Wang Li , Zhang Hui , Qian Haifeng , Qi Xiguang 
Published: March 2020

AbstractAlligator weed (Alternanthera philoxeroides) is a stoloniferous, amphibious and perennial herb which has invaded many parts of the world and led to serious environmental and ecological problems. In order to exploit cheap carbon source for poly(3‐hydroxybutyrate) (PHB) production, alligator weed hydrolysates were prepared by acid and enzyme treatment and used for PHB production via Cupriavidus necator. The bacterium utilized alligator weed enzymatic hydrolysate and produced the PHB concentration of 3.8 ± 0.2 g/L at the conditions of pH 7.0, 27.5°C, 1.5 g/L of nitrogen source, and 25 g/L of carbon source, this exceeded the value of 2.1 ± 0.1 g/L from acid hydrolysate media at the same conditions. In order to obtain the optimum conditions of PHB production, response surface methodology was employed which improved PHB content. The optimum conditions for PHB production are as follows: carbon source, 34 g/L; nitrogen source, 2 g/L; pH, 7; temperature, 28°C. After 72 hr of incubation, the bacterium produced 8.5 g/L of dry cell weight and 4.8 g/L of PHB. The PHB was subjected to Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and Molecular weight analysis and found the melting temperature, number average molecular mass, and polydispersity were 168.20°C, 185 kDa, and 2.1, respectively.
Distinct impacts of financial scarcity and natural resource scarcity on sustainable choices and motivations
Authors: Sachdeva Sonya , Zhao Jiaying 
Published: March 2020

AbstractThe current study examined how financial scarcity and natural resource scarcity independently and interactively influence sustainable choices and motivations. Participants performed a shopping task where they chose between sustainable and conventional products, and rated their motivations for their choice. We found that financial scarcity reduced sustainable product choices, lowered pro‐environmental motivations, but increased motivations to save financial costs (Experiment 1). In contrast, perceived scarcity of natural resources (i.e., water) increased sustainable choices and pro‐environmental motivations (Experiment 2). By combining financial and water scarcity, we further replicated and highlighted the distinct impacts of financial scarcity and water scarcity on sustainable choices and motivations (Experiment 3). Our results suggest that the abundance of financial resources or perceived natural resource scarcity can increase green consumer choices and motivations. The findings provide implications for environmental initiatives and campaigns to promote sustainable choices for people with different socio‐economic backgrounds and different levels of environmental resources.
Synthesis, Biological Evaluation and Molecular Docking of Deferasirox and Substituted 1,2,4‐Triazole Derivatives as Novel Potent Urease Inhibitors: Proposing Repositioning Candidate
Authors: Salehi Ashani Razieh , Azizian Homa , Sadeghi Alavijeh Nahid , Fathi Vavsari Vaezeh , Mahernia Shabnam , Sheysi Niloofar , Biglar Mahmood , Amanlou Massoud , Balalaie Saeed 
Published: March 2020

AbstractA series of new deferasirox derivatives were synthesized through the reaction of monosubstituted hydrazides with 2‐(2‐hydroxyphenyl)‐4H‐benzo[e][1,3]oxazin‐4‐one. For the first time, deferasirox and some of its derivatives were evaluated for their in vitro inhibitory activity against Jack bean urease. The potencies of the members of this class of compounds are higher than that of acetohydroxamic acid. Two compounds, bearing tetrazole and hydrazine derivatives (bioisoester of carboxylate group), represented the most potent urease inhibitory activity with IC50 values of 1.268 and 3.254 μm, respectively. In silico docking studies were performed to delineate possible binding modes of the compounds with the enzyme, urease. Docking analysis suggests that the synthesized compounds were anchored well in the catalytic site and extending to the entrance of binding pocket and thus restrict the mobility of the flap by interacting with its crucial amino acid residues, CME592 and His593. The overall results of urease inhibition have shown that these target compounds can be further optimized and developed as a lead skeleton for the discovery of novel urease inhibitors
Light‐Driven ATP Regeneration in Diblock/Grafted Hybrid Vesicles
Authors: Kleineberg Christin , Wölfer Christian , Abbasnia Amirhossein , Pischel Dennis , Bednarz Claudia , Ivanov Ivan , Heitkamp Thomas , Börsch Michael , Sundmacher Kai , Vidaković‐Koch Tanja 
Published: March 2020

AbstractLight‐driven ATP regeneration systems combining ATP synthase and bacteriorhodopsin have been proposed as an energy supply in the field of synthetic biology. Energy is required to power biochemical reactions within artificially created reaction compartments like protocells, which are typically based on either lipid or polymer membranes. The insertion of membrane proteins into different hybrid membranes is delicate, and studies comparing these systems with liposomes are needed. Here we present a detailed study of membrane protein functionality in different hybrid compartments made of graft polymer PDMS‐g‐PEO and diblock copolymer PBd‐PEO. Activity of more than 90 % in lipid/polymer‐based hybrid vesicles could prove an excellent biocompatibility. A significant enhancement of long‐term stability (80 % remaining activity after 42 days) could be demonstrated in polymer/polymer‐based hybrids.
Isobiology: A Variational Principle for Exploring Synthetic Life
Authors: Danchin Antoine 
Published: March 2020

AbstractMost developments in synthetic biology try to depart from life as we know it, attempting to create orthogonal constructions. Here, following a variational principle, I try to explore how slight changes in the buildup of cells reveal critical features of life's physics. In a first section, I suggest that we use stable isotopes of the atoms of life to see how living cells fare, beginning with life in heavy water. Subsequently, isotopes of the other main biogenic atoms are suggested as an extension of the variational principle, despite their likely very small influence on the course of biological activity. Finally, two atoms of the second row of Mendeleev's table, boron and fluorine are explored as a further extension of the principle. The use of the former is still in its infancy, whereas the latter, based on existing fluorinases, could open the door to a more general use of halogens in synthetic biology.
Porphyrins as Colorimetric and Photometric Biosensors in Modern Bioanalytical Systems
Authors: Norvaiša Karolis , Kielmann Marc , Senge Mathias O. 
Published: March 2020

AbstractAdvances in porphyrin chemistry have provided novel materials and exciting technologies for bioanalysis such as colorimetric sensor array (CSA), photo‐electrochemical (PEC) biosensing, and nanocomposites as peroxidase mimetics for glucose detection. This review highlights selected recent advances in the construction of supramolecular assemblies based on the porphyrin macrocycle that provide recognition of various biologically important entities through the unique porphyrin properties associated with colorimetry, spectrophotometry, and photo‐electrochemistry.
Supersensitive Multifluorophore RNA‐FISH for Early Virus Detection and Flow‐FISH by Using Click Chemistry
Authors: Raddaoui Nada , Croce Stefano , Geiger Florian , Borodavka Alexander , Möckl Leonhard , Stazzoni Samuele , Viverge Bastien , Bräuchle Christoph , Frischmuth Thomas , Engelke Hanna , Carell Thomas 
Published: March 2020

AbstractThe reliable detection of transcription events through the quantification of the corresponding mRNA is of paramount importance for the diagnostics of infections and diseases. The quantification and localization analysis of the transcripts of a particular gene allows disease states to be characterized more directly compared to an analysis on the transcriptome wide level. This is particularly needed for the early detection of virus infections as now required for emergent viral diseases, e. g. Covid‐19. In situ mRNA analysis, however, is a formidable challenge and currently performed with sets of single‐fluorophore‐containing oligonucleotide probes that hybridize to the mRNA in question. Often a large number of probe strands (>30) are required to get a reliable signal. The more oligonucleotide probes are used, however, the higher the potential off‐target binding effects that create background noise. Here, we used click chemistry and alkyne‐modified DNA oligonucleotides to prepare multiple‐fluorophore‐containing probes. We found that these multiple‐dye probes allow reliable detection and direct visualization of mRNA with only a very small number (5–10) of probe strands. The new method enabled the in situ detection of viral transcripts as early as 4 hours after infection.
A Minimized Chemoenzymatic Cascade for Bacterial Luciferase in Bioreporter Applications
Authors: Phonbuppha Jittima , Tinikul Ruchanok , Wongnate Thanyaporn , Intasian Pattarawan , Hollmann Frank , Paul Caroline E. , Chaiyen Pimchai 
Published: March 2020

AbstractBacterial luciferase (Lux) catalyzes a bioluminescence reaction by using long‐chain aldehyde, reduced flavin and molecular oxygen as substrates. The reaction can be applied in reporter gene systems for biomolecular detection in both prokaryotic and eukaryotic organisms. Because reduced flavin is unstable under aerobic conditions, another enzyme, flavin reductase, is needed to supply reduced flavin to the Lux‐catalyzed reaction. To create a minimized cascade for Lux that would have greater ease of use, a chemoenzymatic reaction with a biomimetic nicotinamide (BNAH) was used in place of the flavin reductase reaction in the Lux system. The results showed that the minimized cascade reaction can be applied to monitor bioluminescence of the Lux reporter in eukaryotic cells effectively, and that it can achieve higher efficiencies than the system with flavin reductase. This development is useful for future applications as high‐throughput detection tools for drug screening applications.
Long‐term clinical effects of recanalization of chronic coronary total occlusions in patients with left ventricular systolic dysfunction
Authors: Pinto Giuseppe , Fragasso Gabriele , Gemma Marco , Bertoldi Letizia , Salerno Anna , Godino MD Cosmo , Colombo Antonio , Azzalini Lorenzo , Margonato Alberto , Carlino Mauro 
Published: March 2020

AbstractObjectivesThe aim of the present analysis is to evaluate the clinical impact of chronic total occlusions (CTOs) recanalization in patients with left ventricular (LV) systolic dysfunction.BackgroundAccording to contemporary knowledge, patient selection for percutaneous CTO revascularization is not yet standardized. In particular, data on outcomes in patients with LV systolic dysfunction undergoing percutaneous coronary intervention (PCI) for CTO are scarce.MethodsFrom a total of 2,421 consecutive patients with at least one CTO, 436 patients with ejection fraction (EF) ≤45%, who were referred for coronary angiography between January 1998 and September 2014, were selected. Patients with successful recanalization of the target CTO were assigned to CTO‐revascularized group and those with failed or not attempted recanalization to the CTO‐not revascularized (CTO‐NR) group. Study endpoints were all‐cause death, cardiac death, and occurrence of myocardial infarction on follow‐up.ResultsOut of 436 CTO patients with reduced EF, 228 (52.3%) were successfully recanalized and 208 patients (47.7%) were not, either due to CTO‐PCI failure (n = 106, 24.3%) or because CTO‐PCI was not attempted (n = 102, 23.4%). At long‐term follow‐up, CTO‐NR patients had significantly higher rate of overall (p = .021) and cardiac mortality (p = .035) compared to those successfully revascularized.ConclusionIn patients with systolic LV dysfunction (EF ≤ 45%), CTO revascularization was associated with significant lower rate of total and cardiac mortality compared to those with nonrevascularized CTO.
Zero‐Order Catalysis in TAML‐Catalyzed Oxidation of Imidacloprid, a Neonicotinoid Pesticide
Authors: Warner Genoa R. , Somasundar Yogesh , Weng Cindy , Akin Mete H. , Ryabov Alexander D. , Collins Terrence J. 
Published: March 2020

AbstractBis‐sulfonamide bis‐amide TAML activator [Fe{4‐NO2C6H3‐1,2‐(NCOCMe2NSO2)2CHMe}]− (2) catalyzes oxidative degradation of the oxidation‐resistant neonicotinoid insecticide, imidacloprid (IMI), by H2O2 at pH 7 and 25 °C, whereas the tetrakis‐amide TAML [Fe{4‐NO2C6H3‐1,2‐(NCOCMe2NCO)2CF2}]− (1), previously regarded as the most catalytically active TAML, is inactive under the same conditions. At ultra‐low concentrations of both imidacloprid and 2, 62 % of the insecticide was oxidized in 2 h, at which time the catalyst is inactivated; oxidation resumes on addition of a succeeding aliquot of 2. Acetate and oxamate were detected by ion chromatography, suggesting deep oxidation of imidacloprid. Explored at concentrations [2]≥[IMI], the reaction kinetics revealed unusually low kinetic order in 2 (0.164±0.006), which is observed alongside the first order in imidacloprid and an ascending hyperbolic dependence in [H2O2]. Actual independence of the reaction rate on the catalyst concentration is accounted for in terms of a reversible noncovalent binding between a substrate and a catalyst, which usually results in substrate inhibition when [catalyst]≪[substrate] but explains the zero order in the catalyst when [2]>[IMI]. A plausible mechanism of the TAML‐catalyzed oxidations of imidacloprid is briefly discussed. Similar zero‐order catalysis is presented for the oxidation of 3‐methyl‐4‐nitrophenol by H2O2, catalyzed by the TAML analogue of 1 without a NO2‐group in the aromatic ring.
NCP‐Type Pincer Iridium Complexes Catalyzed Transfer‐Dehydrogenation of Alkanes and Heterocycles†
Authors: Wang Yulei , Qian Lu , Huang Zhidao , Liu Guixia , Huang Zheng 
Published: March 2020

Summary of main observation and conclusionA series of NCP‐type pincer iridium complexes, (RNCCP)IrHCl (2a—2c) and (BQ‐NCOP)IrHCl 3, have been studied for catalytic transfer alkane dehydrogenation. Complex 3 containing a rigid benzoquinoline backbone exhibits high activity and robustness in dehydrogenation of alkanes to form alkenes. Even more importantly, this catalyst system was also highly effective in the dehydrogenation of a wide range of heterocycles to furnish heteroarenes.
Rapid Discovery of Aspartyl Protease Inhibitors Using an Anchoring Approach
Authors: Konstantinidou Markella , Magari Francesca , Sutanto Fandi , Haupenthal Jörg , Jumde Varsha R. , Ünver M. Yagiz , Heine Andreas , Camacho Carlos Jamie , Hirsch Anna K. H. , Klebe Gerhard , Dömling Alexander 
Published: March 2020

AbstractPharmacophore searches that include anchors, fragments contributing above average to receptor binding, combined with one‐step syntheses are a powerful approach for the fast discovery of novel bioactive molecules. Here, we are presenting a pipeline for the rapid and efficient discovery of aspartyl protease inhibitors. First, we hypothesized that hydrazine could be a multi‐valent warhead to interact with the active site Asp carboxylic acids. We incorporated the hydrazine anchor in a multicomponent reaction and created a large virtual library of hydrazine derivatives synthetically accessible in one‐step. Next, we performed anchor‐based pharmacophore screening of the libraries and resynthesized top‐ranked compounds. The inhibitory potency of the molecules was finally assessed by an enzyme activity assay and the binding mode confirmed by several soaked crystal structures supporting the validity of the hypothesis and approach. The herein reported pipeline of tools will be of general value for the rapid generation of receptor binders beyond Asp proteases.