The crystal structure of Escherichia coli methionyl-tRNAfMet transformylase complexed with formyl-methionyl-tRNAfMet was solved at 2.8 A resolution. The formylation reaction catalyzed by this enzyme irreversibly commits methionyl-tRNAfMet to initiation of translation in eubacteria. In the three-dimensional model, the methionyl-tRNAfMet formyltransferase fills in the inside of the L-shaped tRNA molecule on the D-stem side. The anticodon stem and loop are away from the protein. An enzyme loop is wedged in the major groove of the acceptor helix. As a result, the C1-A72 mismatch characteristic of the initiator tRNA is split and the 3' arm bends inside the active centre. This recognition mechanism is markedly distinct from that of elongation factor Tu, which binds the acceptor arm of aminoacylated elongator tRNAs on the T-stem side.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1171029 | PMC |
http://dx.doi.org/10.1093/emboj/17.23.6819 | DOI Listing |
Environ Sci Technol
January 2025
Geomicrobiology, Department of Geosciences, University of Tübingen, Tübingen 72076, Germany.
Defects are common features in hematite that arise from deviations from the perfect mineral crystal structure. Vacancy defects have been shown to significantly enhance arsenate (As) immobilization by hematite. However, the contributions from vacancy defects on different exposed facets of hematite have not been fully quantified.
View Article and Find Full Text PDFChem Sci
January 2025
Research Institute for Science & Technology, Tokyo University of Science Tokyo 162-8601 Japan
The scarcity of approaches to assembling copper nanoclusters (Cu NCs) has restricted advancements in Cu NCs research, largely due to stability challenges of the individual NCs. By utilizing the structural adaptability of Cu NCs, we systematically investigate how variations in organic linkers and solvents affect the cluster node size, shape, and their assembling dimensionality. Here, we introduce a facile, one-pot synthesis method for obtaining a range of crystalline Cu cluster-assembled materials (CAMs) through a liquid-liquid interfacial crystallization technique.
View Article and Find Full Text PDFChem Sci
January 2025
College of Chemistry and Materials Engineering, Wenzhou University Wenzhou 325035 P. R. China
O3-type NaNiMnO cathode material exhibits significant potential for sodium-ion batteries (SIBs) owing to its high theoretical capacity and ample sodium reservoir. Nonetheless, its practical implementation encounters considerable obstacles, such as impaired structural integrity, sensitivity to moisture, inadequate high-temperature stability, and being unstable under high-voltage conditions. This study investigates the co-substitution of Cu, Mg, and Ti, guided by principles of the periodic law, to enhance the material's stability under varying conditions.
View Article and Find Full Text PDFRSC Adv
January 2025
ICMR-Regional Medical Research Centre, Department of Health Research, Ministry of Health & Family Welfare, Govt. of India Bhubaneswar 751023 Odisha India.
Palladium-catalyzed reactions between imidazo[1,2-]pyridine derivatives and 4-bromo-2,2-dialkyl-substituted 2-chromenes under microwave irradiation at 100 W, 120 °C for 20-30 min provided a series of new 3-(2,2-dialkyl-2-chromen-4-yl)-2-phenylimidazo[1,2-]pyridine derivatives in good to excellent yields. The structures of the synthesized compounds were confirmed through spectroscopic techniques (NMR and HRMS). The X-ray single-crystal structure of compound 16e was also determined.
View Article and Find Full Text PDFDalton Trans
January 2025
Instituto de Ciencia de Materiales de Madrid (ICMM), CSIC, Madrid, Spain.
A pure silica zeolite with structure was synthesized using the tricyclopentylmethylphosphonium (CpMP) cation under fluoride media. Analysis of the organic content in the zeolite suggested the presence of more than four cations per unit cell, while fluoride anions were exclusively located in the four double four-membered rings of the structure. Si solid-state NMR demonstrated a significant concentration of Si species, , S̲i̲(OSi)(OH), in the structure, which afforded charge balance but contrasted with the most common observation of defect-free pure silica zeolites prepared in fluoride media at near-neutral pH.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!