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101.
Yaoyu Ren Timo Danner Alexandra Moy Martin Finsterbusch Tanner Hamann Jan Dippell Till Fuchs Marius Müller Ricky Hoft André Weber Larry A. Curtiss Peter Zapol Matthew Klenk Anh T. Ngo Pallab Barai Brandon C. Wood Rongpei Shi Liwen F. Wan Tae Wook Heo Martin Engels Jagjit Nanda Felix H. Richter Arnulf Latz Venkat Srinivasan Jürgen Janek Jeff Sakamoto Eric D. Wachsman Dina Fattakhova-Rohlfing 《Liver Transplantation》2023,13(1):2201939
The garnet-type phase Li7La3Zr2O12 (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid-state batteries (SSBs) with potentially high energy density. However, while significant progress has been made in demonstrating compatibility with Li metal, integrating LLZO into composite cathodes remains a challenge. The current perspective focuses on the critical issues that need to be addressed to achieve the ultimate goal of an all-solid-state LLZO-based battery that delivers safety, durability, and pack-level performance characteristics that are unobtainable with state-of-the-art Li-ion batteries. This perspective complements existing reviews of solid/solid interfaces with more emphasis on understanding numerous homo- and heteroionic interfaces in a pure oxide-based SSB and the various phenomena that accompany the evolution of the chemical, electrochemical, structural, morphological, and mechanical properties of those interfaces during processing and operation. Finally, the insights gained from a comprehensive literature survey of LLZO–cathode interfaces are used to guide efforts for the development of LLZO-based SSBs. 相似文献
102.
Moesgaard B. Errebo Larsen I. Quistorff B. Therkelsen I. Christensen V. Grøsfjeld Jørgensen P. Fogd 《Acta veterinaria Scandinavica》1993,34(4):397-404
The effect of dietary magnesium on the post mortem PCr (phosphocreatine) decay in muscle of heterozygote malignant hyperthermia pigs was studied after in vivo exposure to a combination of halothane and succinylcholine. The pigs were anaesthetized with halothane and succinylcholine was injected in the ear vein. Immediately after initiation of the depolarizing neuromuscular blocking effect of succinylcholine the animals were captive-bolt stunned. The PCr decay, reflecting ATP turnover, was followed in situ by 31P-NMR spectroscopy in the biceps femoris muscle for the subsequent 40-70 min post mortem. In 3 of the 4 experiments, the Mg-fed pig had a significantly reduced rate of PCr hydrolysis compared to the control animal. The mechanism of this magnesium effect is unknown. 相似文献
103.
Matthias Kronen Helmar G?rls Hoai-Huong Nguyen Siegmund Reissmann Martin Bohl Jürgen Sühnel Udo Gr?fe 《Journal of peptide science》2003,9(11-12):729-744
Ampullosporin A is a 15-mer peptaibol type polypeptide that induces pigment formation by the fungus Phoma destructiva, forms voltage-dependent ion channels in membranes and exhibits hypothermic effects in mice. The structure of ampullosporin A has been determined by x-ray crystallography. This is the first three-dimensional (3D) structure of the peptaibol subfamily SF6. From the N-terminus to residue 13 the molecule adopts an approximate right-handed alpha-helical geometry, whereas a less regular structure pattern with beta-turn characteristics is found in the C-terminus. Even though ampullosporin A does not contain a single proline or hydroxyproline it is significantly bent. It belongs to both the shortest and the most strongly bent peptaibol 3D structures. The straight structure part encompasses residues Ac-Trp(1)-Aib(10) and is thus less extended than the alpha-helical subunit. The 3D structure of ampullosporin A is discussed in relation to other experimentally determined peptaibol structures and in the context of its channel-forming properties. As a part of this comparison a novel bending analysis based on a 3D curvilinear axis describing the global structural characteristics has been proposed and applied to all 3D peptaibol structures. A sampling of 2500 conformations using different molecular dynamics protocols yields, for the complete ampullosporin A structure, an alpha-helix as the preferred conformation in vacuo with almost no bend. This indicates that solvent or crystal effects may be important for the experimentally observed peptide backbone bending characteristics of ampullosporin A. 相似文献
104.
Grégoire Levasseur Marie-Annick Persuy Denise Grebert Jean-Jacques Remy Roland Salesse Edith Pajot-Augy 《European journal of biochemistry》2003,270(13):2905-2912
Primary olfactory neuronal cultures exposed to odorant stimulation have previously exhibited concentration-related effects in terms of intracellular cAMP levels and adenylate cyclase activity [Ronnett, G.V., Parfitt, D.J., Hester, L.D. & Snyder, S.H. (1991) PNAS88, 2366-2369]. Maximal stimulation occurred for intermediate concentrations, whereas AC activity declined for both low and high odorant concentrations. We suspected that this behavior might be ascribed to the intrinsic response of the first molecular species concerned by odorant detection, i.e. the olfactory receptor itself. In order to check this hypothesis, we developed an heterologous expression system in mammalian cells to characterize the functional response of receptors to odorants. Two mammalian olfactory receptors were used to initiate the study, the rat I7 olfactory receptor and the human OR17-40 olfactory receptor. The cellular response of transfected cells to an odorant stimulation was tested by a spectrofluorimetric intracellular calcium assay, and proved in all cases to be dose-dependent for the known ligands of these receptors, with an optimal response for intermediate concentrations. Further experiments were carried out with the rat I7 olfactory receptor, for which the sensitivity to an odorant, indicated by the concentration yielding the optimal calcium response, depended on the carbon chain length of the aldehydic odorant. The response is thus both ligand-specific and dose-dependent. We thus demonstrate that a differential dose-response originates from the olfactory receptor itself, which is thus capable of efficient discrimination between closely related agonists. 相似文献
105.
106.
M. Atta Noële Debaecker K. K. Andersson Jean-Marc Latour Lars Thelander Astrid Gräslund 《Journal of biological inorganic chemistry》1996,1(3):210-220
Mouse ribonucleotide reductase is composed of a 1?:?1 complex of two homodimeric subunits and catalyses the first unique step on the biochemical pathway to DNA synthesis. The small subunit, protein R2, contains dinuclear iron-oxygen clusters and a tyrosyl free radical required for catalytic activity. We have studied the mixed valent and fully reduced forms of the diiron oxygen cluster from mouse R2 protein by low-temperature EPR. EPR signals of the mixed-valent states of proteins R2 reconstituted with ferrous iron and oxygen in normal and deuterated water, using the same buffers, show apparent g values of 1.92, 1.73, and 1.60 for the mixed-valent state in H2O and 1.93, 1.73, and 1.62 in D2O. These g values are typical for diiron-oxygen proteins, while the effect of D2O is unprecedented for this class of proteins. We estimate the coupling constant J for the Heisenberg exchange (H?=?2J*S1*S2) to be J?=?–7.5±1?cm–1 for the mixed-valent form. The diferrous R2 protein shows an integer spin EPR signal in the presence of azide or 20% glycerol. Variable temperature variable field saturation magnetisation measurements show that only in the azide-complexed R2 protein does a weak ferromagnetic coupling occur (J?=?0.26±0.05?cm–1), while R2 protein in the absence or presence of 20% glycerol contains non-coupled mononuclear ferrous iron (S?=?2) sites. 相似文献
107.
Mohamed Benichou Gracia Martinez-Reina Felix Romojaro Jean-Claude Pech Alain Latché 《Physiologia plantarum》1995,94(4):629-634
A 36-kDa 1-aminocyclopropane-1-carboxylate (ACC) N-malonyltransferase, which converts the ethylene precursor ACC into the conjugated derivative malonyl-ACC (MACC), has been isolated from etiolated mung bean ( Vigna radiata ) hypocotyls, and partially purified in a four-step procedure. The enzyme is stimulated about 7-fold by 100 m M K+ salts or 0.5 m M Co2+ salts, and is inhibited competitively by D-phenylalanine (Ki = 1.3 m M ) and non competitively by CoASH (0.3 m M ). Beside malonyl-CoA, it is capable to use succinyl-CoA as an acyl donor. The 36-kDa enzyme described here exhibits a lower optimum temperature (40°C) and a 7- or 3-fold lower apparent Km for ACC (68 μ M ) and malonyl-CoA (74 μ M ), respectively, when compared with its 55 kDa isoform already isolated from the same plant material. This data support the idea that several isoforms of ACC N-malonyltransferase exist in plants. These isoforms may play a differential role in regulating the availability of ACC, and consequently the rate of ethylene production, as well as detoxifying cells from D-amino acids. 相似文献
108.
NMR solution structure of a dsRNA binding domain from Drosophila staufen protein reveals homology to the N-terminal domain of ribosomal protein S5. 总被引:7,自引:3,他引:4 下载免费PDF全文
The double-stranded RNA binding domain (dsRBD) is an approximately 65 amino acid motif that is found in a variety of proteins that interact with double-stranded (ds) RNA, such as Escherichia coli RNase III and the dsRNA-dependent kinase, PKR. Drosophila staufen protein contains five copies of this motif, and the third of these binds dsRNA in vitro. Using multinuclear/multidimensional NMR methods, we have determined that staufen dsRBD3 forms a compact protein domain with an alpha-beta-beta-beta-alpha structure in which the two alpha-helices lie on one face of a three-stranded anti-parallel beta-sheet. This structure is very similar to that of the N-terminal domain of a prokaryotic ribosomal protein S5. Furthermore, the consensus derived from all known S5p family sequences shares several conserved residues with the dsRBD consensus sequence, indicating that the two domains share a common evolutionary origin. Using in vitro mutagenesis, we have identified several surface residues which are important for the RNA binding of the dsRBD, and these all lie on the same side of the domain. Two residues that are essential for RNA binding, F32 and K50, are also conserved in the S5 protein family, suggesting that the two domains interact with RNA in a similar way. 相似文献
109.
110.
Effects of cadmium,copper, and zinc on growth and thiol content of aquatic hyphomycetes 总被引:3,自引:1,他引:2
The effects of cadmium, copper, and zinc on the growth of ten strains ofaquatic hyphomycetes were investigated. On a solid medium, Cd and Cu reducedradial growth of most strains by 50% at concentrations between150–400 µM; in a liquid medium, the strains were more sensitive.The inhibitory effects of zinc were much less severe. Two isolates(Articulospora tetracladia and Tetracladium marchalianum) from a copper-minestream were more resistant against copper than conspecific strains from anon-polluted stream. Heliscus lugdunensis and Varicosporium elodeaeresponded to Cd exposure, but not to Cu or Zn exposure, by increasedsynthesis of SH-containing compounds. Glutathione levels showed a unimodalresponse to increasing Cd and Zn exposure. With copper, glutathionedecreased at intermediate levels of contamination. In the presence of Cd, H. lugdunensis synthesized several unknown sulfur-rich substances that wereabsent or produced at reduced rates in control cultures. 相似文献