A set of 45 different tRNAs, each containing a single deoxynucleotide substitution covering the upper half of the molecule was used in conjunction with a high-throughput ribonuclease protection assay to investigate the thermodynamic role of 2' hydroxyl groups in stabilizing a complex with elongation factor Tu (EF-Tu) from Thermus thermophilus. Five distinct 2' hydroxyl groups were identified wh...

The anti-microbial activity of calcium hydroxide pastes used in endodontics is dependent on establishing high levels of hydroxyl ions in dentine. This study investigated hydroxyl ion diffusion from different commercial calcium hydroxide pastes using a novel colourimetric method. In this method, human tooth roots were stained with anthocyanin dye, which changed their colour according to the loca...

The exchange of water hydroxyl hydrogen bonds between anions and water oxygens is observed directly with ultrafast 2D IR vibrational echo chemical exchange spectroscopy (CES). The OD hydroxyl stretch of dilute HOD in H(2)O in concentrated (5.5 M) aqueous solutions of sodium tetrafluoroborate (NaBF(4)) displays a spectrum with a broad water-like band (hydroxyl bound to water oxygen) and a resolv...

Fourier Transform infrared (FTIR) absorption spectra of hydroxyl were measured on olivine phenocrysts from hydrous basaltic melts that originated in island-arc tectonic settings. The basaltic melts encompass a wide range of silica activities from orthopyroxene-saturated hypersthene-normative to nepheline-normative compositions. The intensities and wavenumber placement of hydroxyl absorption ban...

Effect of caffeic acid on the formation of hydroxyl radicals was examined during xanthone-mediated photosensitization. The reaction was performed on irradiation (lambda = 365 nm) of the standard reaction mixture containing 15 microM xanthone, 0.1 M 5,5-dimethyl-1-pyrroline N-oxide (DMPO) and 20 mM phosphate buffer (pH 7.4) using electron paramagnetic resonance (EPR) with spin trapping. Caffeic ...

The concentrations of hydroxyl groups located inside and on the surface oxide films of a commercially pure titanium, cp-Ti, a type 316L austenitic stainless steel, SS, and a cobalt-chromium-molybdenum alloy, Co-Cr-Mo, were evaluated using X-ray photoelectron spectroscopy, XPS, and a zinc-complex substitution technique. As a result, the concentrations of the hydroxyl groups detected by the zinc-...

The reason for these questions lies in the fact that the pH, or degree of acidity of the soil, often is a symptom of some disorder in the chemical condition of the soil as it relates to plant nutrition. A measurement of soil acidity or alkalinity is like a doctor's measurement of a patient's temperature. It reveals that something naay be wrong but it does not tell the exact nature of the troubl...

Cellular exposure to particulate matter with concomitant formation of reactive oxygen species (ROS) and oxidization of biomolecules may lead to negative health outcomes. Evaluating the particle-induced formation of ROS and the oxidation products from reaction of ROS with biomolecules is useful for gaining a mechanistic understanding of particle-induced oxidative stress. Aqueous suspensions of p...

Monolayers presenting methyl-terminated (hydrophobic) and hydroxyl-terminated (hydrophilic) surfaces on silica have been studied by molecular dynamics simulation and the effects of hydrogen bonding, chain length, and chain mixing on the frictional properties determined. The hydroxyl-terminated monolayers were found to show large adhesion zones as a result of strong interfacial interlayer hydrog...

Conversion of pyrogallol to phloroglucinol was studied with the molybdenum enzyme transhydroxylase of the strictly anaerobic fermenting bacterium Pelobacter acidigallici. Transhydroxylation experiments in H218O revealed that none of the hydroxyl groups of phloroglucinol was derived from water, confirming the concept that this enzyme transfers a hydroxyl group from the cosubstrate 1,2,3, 5-tetra...