98%
921
2 minutes
20
The stability of the mercury ion mediated dU-Hg-dU pair depends on substituents introduced at the 5-position of the pyrimidine moiety. To this end, a series of oligonucleotides were synthesized with dU modification in central position. Common and new phosphoramidites were utilized. Hybridization experiments provided 12-mer duplexes with non-canonical "dU-dU" pairs. In most cases Hg stabilizes duplexes by metal ion mediated base pair formation identified by higher duplex melting. Among the three types of dU derivatives incorporated in duplex DNA those with small aliphatic side chains have only a minor impact on the stability of the mercury-mediated base pair, while those with a triple bond in the side chain show hysteresis during duplex heating and cooling cycle implying triple bond interaction with mercury ions. Formation of metal ion mediated base pairs is blocked by space occupying aromatic side chains by side chain-helix stacking interactions. These interactions are too strong to permit mercury ion mediated base pair formation and drive the uridine N(3) acceptor atoms in an unfavorable pairing position.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1039/c6ob02560a | DOI Listing |
Lasers Med Sci
September 2025
Laser Research Center of Dentistry, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
Microbial contamination of absorbable collagen membranes used in guided bone regeneration (GBR) may compromise healing outcomes. This study aimed to investigate whether the minimum inhibitory concentration (MIC) of hydrogen peroxide (HO) can improve the antibacterial effect of indocyanine green (ICG)-mediated antimicrobial photodynamic therapy (PDT) on absorbable collagen membranes while reducing the need for high HO concentrations. A laboratory-based model was developed using Streptococcus sanguinis and Staphylococcus aureus.
View Article and Find Full Text PDFAdv Sci (Weinh)
September 2025
State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, 266071, China.
Pufferfish exhibit the smallest vertebrate genomes, making them ideal models for investigating evolutionary patterns and processes that affect genome size. While the Takifugu rubripes genome was fully sequenced two decades ago, key evolutionary drivers remain elusive. We sequenced 10 pufferfish genomes and generated 35 transcriptomes and 13 methylomes to understand genomic evolutionary mechanisms.
View Article and Find Full Text PDFiScience
September 2025
Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, 46022 Valencia, Spain.
Arbuscular mycorrhizal fungi (AMF) play a crucial role in disease control by establishing symbiotic relationships with plant roots. AMF improve salinity tolerance in plants by regulating the Na/K ratio through selective ion transport and mediate osmotic regulation by inducing the accumulation of osmotic-compatible solutes such as glycine betaine and proline to enable plant cells to maintain water content and the metabolic balance. AMF can also activate antioxidant defense responses by stimulating enzymes that protect plant cells from harmful oxidation and pathological infections.
View Article and Find Full Text PDFACS Electrochem
September 2025
Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, Wood Lane, London W12 0BZ, United Kingdom.
The development of copper-catalyzed C-H functionalization processes is challenging due to the inefficiency of conventional chemical oxidants in regenerating the copper catalyst. This study details the development of a mediated electrosynthetic approach involving triple catalytic cycles in transient C-H functionalization to achieve efficient copper-catalyzed C-(sp)-H sulfonylation of benzylamines with sodium sulfinate salts. The triple catalytic system consists of a copper organometallic cycle for C-H functionalization, an aldehyde transient directing group (TDG) as an organocatalyst for imine formation, and a ferrocenium salt as an electrocatalyst.
View Article and Find Full Text PDFBeilstein J Org Chem
August 2025
Department of Chemistry, Institute of Natural Sciences, Federal University of Lavras, 37200-900, Lavras, MG, Brazil.
Cyclopropane is a significant alicyclic motif, widely utilized in medicinal chemistry, while fluorination serves as a powerful tool to modulate properties that enhance the performance of pharmaceuticals and materials. This quantum-chemical study explores the energetic implications of fluorinating cyclopropane, providing insights into molecular characteristics arising from the polar C-F bond. Isodesmic reactions revealed that the conversion of cyclopropane and methyl fluoride into mono-, di-, tri-, tetra-, penta-, and hexafluorinated cyclopropanes is exothermic, except for the all--1,2,3-trifluorocyclopropane ().
View Article and Find Full Text PDF