In vitro selection was used to isolate five classes of allosteric hammerhead ribozymes that are triggered by binding to certain divalent metal ion effectors. Each of these ribozyme classes are similarly activated by Mn2+, Fe2+, Co2+, Ni2+, Zn2+ and Cd2+, but their allosteric binding sites reject other divalent metals such as Mg2+, Ca2+ and Sr2+. Through a more comprehensive survey of cations, i...

The response of allanite-(Ce) in the Eocene Casto granite of Idaho to hydrothermal activity has been investigated. Unaltered, igneous allanite from the Casto pluton is characterized by a narrow range of compositional variation, with little or no zoning. A representative empirical formula, based on the composition of the least-altered grain, is: (REE0.83Ca1.07Th0.04Mn0.06) (Ti0.11 Mg0.04Fe0.99Fe...

The herpes simplex virus type 1 (HSV-1) latency-associated transcript (LAT) is abundantly expressed in latently infected sensory neurons. In small animal models of infection, expression of the first 1.5 kb of LAT coding sequences is necessary and sufficient for wild-type reactivation from latency. The ability of LAT to inhibit apoptosis is important for reactivation from latency. Within the fir...

A recent proposal (Clin Chem 1992;38:1809-18) that inorganic phosphate is the predominant small molecule binding Al3+ in blood serum is shown to be incorrect. Experiments in which Al3+ is added to solutions containing phosphate and citrate in the same proportions as in serum clearly show that citrate prevents formation of any aluminum phosphate precipitate, and analysis of these data indicates ...

OBJECTIVES Metals such as iron are needed for physiological functions of the body. However, their excess may cause serious damage including poisoning. The effects of Fe2+ and Fe3+ ions on human plasma cholinesterase activity were investigated. MATERIAL AND METHODS Plasma were obtained (n = 24) from healthy male volunteers, and treated with five various concentrations of Fe2+ and Fe3+ ions. Ac...

Our former study reported that Fe-Sn spinel (Fe3-xSnxO4) was easily formed when SnO2 and Fe3O4 were roasted under CO-CO2 atmosphere at 900-1100 °C. However, the formation procedure is still unclear and there is a lack of theoretical research on the formation mechanism of the Fe-Sn spinel. In this work, the reaction mechanisms between SnO2 and Fe3O4 under CO-CO2 atmosphere were determined using ...

Under iron-limited conditions, Pseudomonas putida WCS358 produces a siderophore, pseudobactin 358, which is essential for the plant growth-stimulating ability of this strain. Cells of strain WCS358, provided that they have been grown under Fe3+ limitation, take up 55Fe3+ from the 55Fe3+-labeled pseudobactin 358 complex with Km and Vmax values of 0.23 microM and 0.14 nmol/mg of cell dry weight p...

Modeling metalloproteins often requires classical molecular dynamics (MD) simulations in order to capture their relevant motions, which in turn necessitates reliable descriptions of the metal centers involved. One of the most successful approaches to date is provided by the "cationic dummy model", where the positive charge of the metal ion is transferred toward dummy particles that are bonded t...

W-type hexaferrites were discovered in the 1950s and are of interest for their potential applications. In this context, many researchers have conducted studies on partial substitution Fe sites order to modify electric magnetic properties. study, SrYb using Al3+ as substitutes Fe3+ with nominal composition Sr0.85Yb0.15Zn1.5Co0.5AlxFe16−xO27 (0.00 ≤ x 1.25) successfully synthesized via two-step c...

Aluminum (Al) toxicity is the primary factor limiting crop growth in acidic soils. Boron (B) alleviates Al toxicity in plants, which is mainly considered to be due to the formation of Rhamnogalacturonan II-B (RGII-B) complexes, which helps to stabilize the cytoskeleton. It is unclear yet whether this is due to the increasing of net negative charges and/or further mechanisms. Kinetics of Al accu...