Yuurquhart0756

Z Iurium Wiki

Marine algae are a major source of ω-3 long-chain polyunsaturated fatty acids (ω3-LCPUFAs), which are conditionally essential nutrients in humans and a target for industrial production. The biosynthesis of these molecules in marine algae requires the desaturation of fatty acids by Δ6-desaturases, and enzymes from different species display a range of specificities toward ω3- and ω6-LCPUFA precursors. In the absence of a molecular structure, the structural basis for the variable substrate specificity of Δ6-desaturases is poorly understood. Here we have conducted a consensus mutagenesis and ancestral protein reconstruction-based analysis of the Δ6-desaturase family, focusing on the ω3-specific Δ6-desaturase from Micromonas pusilla (MpΔ6des) and the bispecific (ω3/ω6) Δ6-desaturase from Ostreococcus tauri (OtΔ6des). Our characterization of consensus amino acid substitutions in MpΔ6des revealed that residues in diverse regions of the protein, such as the N-terminal cytochrome b5 domain, can make important contributions to determining substrate specificity. Ancestral protein reconstruction also suggests that some extant Δ6-desaturases, such as OtΔ6des, could have adapted to different environmental conditions by losing specificity for ω3-LCPUFAs. This data set provides a map of regions within Δ6-desaturases that contribute to substrate specificity and could facilitate future attempts to engineer these proteins for use in biotechnology.Antimony (Sb) has been considered as a promising anode for sodium ion batteries (SIBs) due to its high theoretical capacity and moderate working potential, but suffers from the dramatic volume variations (~250%), unstable electrode/electrolyte interphase and active material exfoliation, and continuously increased interphase impedance upon sodiation and desodiation processes. To address these issues, we report a unique 3D porous self-standing foam electrode built from core-shelled Sb@In2O3 nanostructures via a continuous electrodepositing strategy coupled with surface chemical passivation. Such a hierarchical structure possesses a robust framework with rich voids and a dense protection layer (In2O3), which allow Sb nanoparticles to well accommodate their mechanical strain for efficiently avoiding electrode cracks and pulverization with stable electrode/electrolyte interphase upon sodiation/de-sodiation processes. When evaluated as anode for SIBs, the prepared nanoarchitectures exhibit a high first reversible capacity (641.3 mAh g-1) and good cyclability (456.5 mAh g-1 after 300 cycles at 300 mA g-1), simultaneously with superior high-rate capacity (348.9 mAh g-1 even at 20 A g-1) with a first coulomb efficiency as high as 85.3%. Such work could offer an efficient approach to improve alloying-based anode materials for promoting their practical application.Directional control on material properties such as mechanical moduli or thermal conductivity are of paramount importance for the development of nanostructured next generation devices. Two-dimensional materials are particularly interesting in this context owing to their inherent structural anisotropy. Here, we compare graphene oxide (GO) and synthetic clay sodium fluorohectorite (Hec) with respect to their thermal transport properties. The unique sheet structure of both allows preparing highly ordered Bragg stacks of these pure materials. The thermal conductivity parallel to the platelets strongly exceeds the thermal conductivity perpendicular to them. We find a significant difference in the performance between GO and synthetic clay. Our analysis of the textured structure, size of the platelets and chemical composition shows that Hec is a superior two-dimensional component compared to GO. Consequently, synthetic clay is a promising material for thermal management applications in electronic devices, where electrically insulating materials are prerequisite.Nargenicin A1(1) is an antibacterial macrolide with effective activity against various Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus. Due to the promising properties of this compound in inhibiting cell proliferation, immunomodulation, and the cell protective effect, there has been significant interest in this molecule. Recently, the biosynthetic gene cluster (BGC) of 1 was reported from Nocardia argentinesis and Nocardia arthritidis. In addition, two crucial enzymes involved in the formation of the core decalin moiety and postmodification of the decalin moiety by an ether bridge were characterized. This study reports on the BGC of 1 from Nocardia sp. CS682. In addition, the direct capture and heterologous expression of nar BGC from Nocardia sp. CS682 in Streptomyces venezuelae led to the production of 1. Further metabolic profiling of wild type, Nocardia sp. CS682 in optimized media (DD media) resulted in the isolation of two acetylated derivatives, 18-O-acetyl-nodusmicin and 18-O-acetyl-nargenicin. Chlorogenic Acid in vitro The post-PKS modification pathway in biosynthesis of 1 was also deciphered by identifying intermediates and/or in vitro enzymatic reactions of NgnP1, NgnM, and NgnO3. Different novel analogues of 1, such as compound 6, compound 7, 23-demethyl 8,13-deoxy-nodusmicin (8), 23-demethyl 8,13-deoxynargenicin (9), 8,13-deoxynodusmicin (10), and 8,13-deoxynargenicin (11), were also characterized, which extended our understanding of key post-PKS modification steps during the biosynthesis of 1. In addition, the antimicrobial and anticancer activities of selected analogues were also evaluated, whereas compound 9 was shown to exhibit potent antitumor activity by induction of G2/M cell cycle arrest, apoptosis, and autophagy.Latent tracks in pure polymer and its nanohybrid are fabricated by irradiating with swift heavy ions (SHI) (Ag+) having 140 MeV energy followed by selective chemical etching of the amorphous path, caused by the irradiation of SHI, to generate nanochannels of size ∼80 nm. Grafting is done within the nanochannels utilizing free radicals generated from the interaction of high-energy ions, followed by tagging of ionic species to make the nanochannels highly ion-conducting. The uniform dispersion of two-dimensional nanoparticles better controls the size and number density of the nanochannels and, thereby, converts them into an effective membrane. The nanoparticle and functionalization induce a piezoelectric β-phase in the membrane. The functionalized membrane removes the radioactive nuclide like 241Am+3 (α-emitting source) efficiently (∼80% or 0.35 μg/cm2) from its solution/waste. This membrane act as a corrosion inhibitor (92% inhibition efficiency) together with its higher proton conduction (0.13 S/m) ability. The higher ion-exchange capacity, water uptake, ion conduction, and high sorption by the nanohybrid membrane are explored with respect to the extent of functionalization and control over nanochannel dimension.

Autoři článku: Yuurquhart0756 (Choate Nielsen)