Interconversion of carbon sites in boat-chair-boat (BCB) cyclodecane occurs by way of the twist-boat-chair (TBC) conformation, which predicts that C-1 exchanges with C-4, etc. The previously obtained low-temperature 13C spectra could be matched by assuming (1,4) or (1,3) exchange, but not (1,2) exchange. A free-energy barrier of 5.54 kcal/mol was obtained for conversion of BCB to TBC at -137.4 degrees C. The major conformation of chlorocyclodecane and cyclodecyl acetate is assigned to the IIIe BCB.
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Appl Environ Microbiol
December 2024
State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, Beijing, China.
Unlabelled: Acetate/acetyl-CoA interconversion is an interesting metabolic node, primarily catalyzed by a set of various enzymes in prokaryotes. is a promising haloarchaeaon, capable of utilizing acetate as a sole carbon source for biosynthesis of high value-added products. Here, we have reported the key enzymes that catalyzed acetate activation in .
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January 2025
Department of Chemistry, Seoul National University Seoul 08826 Republic of Korea +82 2 880 6653.
Biological CO/CO interconversion catalyzed at the Ni/Fe heterobimetallic active site of anaerobic carbon monoxide dehydrogenases (CODHs) offers important insights for the design of efficient and selective synthetic catalysts for CO capture and utilization (CCU). Notably, this organometallic C interconversion process is mediated at a three-coordinate nickel site. Extensive research has been conducted to elucidate the redox and structural changes involved in substrate binding and conversion.
View Article and Find Full Text PDFISME Commun
January 2024
GFZ German Research Centre for Geosciences, Section Geomicrobiology, Telegrafenberg, 14473 Potsdam, Germany.
Ferruginous conditions prevailed through Earth's early oceans history, yet our understanding of biogeochemical cycles in anoxic iron-rich, sulfate-poor sediments remains elusive in terms of redox processes and organic matter remineralization. Using comprehensive geochemistry, cell counts, and metagenomic data, we investigated the taxonomic and functional distribution of the microbial subsurface biosphere in Lake Towuti, a stratified ferruginous analogue. Below the zone in which pore water becomes depleted in electron acceptors, cell densities exponentially decreased while microbial assemblages shifted from iron- and sulfate-reducing bacterial populations to fermentative anaerobes and methanogens, mostly selecting Bathyarchaeia below the sulfate reduction zone.
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December 2024
Chemistry Department, Indian Institute of Technology Bombay, Mumbai, Maharashtra, 400076, India.
Bidirectional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) electrocatalysts are key for molecular oxygen-centric renewable energy transduction via metal-air batteries. Here, a molecular cobalt complex is covalently tethered on a strategically functionalized silica surface that displayed both ORR and OER in alkaline media. The detailed X-ray absorbance spectroscopy (XAS) studies indicate that this catalyst retains its intrinsic molecular features while playing a central role during bidirectional electrocatalysis and demonstrating a relatively lower energy gap between O/HO interconversions.
View Article and Find Full Text PDFNutrients
November 2024
School of Nursing, Jinan University, Guangzhou 510632, China.
Objectives: Long-term Western diet-induced non-alcoholic steatohepatitis (NASH) can lead to liver cirrhosis and NASH-associated hepatocellular carcinoma, which are end-stage liver diseases. Meanwhile, NASH is associated with mental burden and worsens as the disease progresses. Atractylodes Macrocephala Koidz (AMK) is one of the main ingredients of Shenling Baizhu San, and the effect of Polysaccharide from AMK ameliorates (PAMK), as an important medicinal ingredient of AMK, on NASH and associated anxiety/depression-like behaviors is still unclear.
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