Aminoacyl-tRNA synthetases (AARS) are essential proteins found in all living organisms. They form a diverse group of enzymes that ensure the fidelity of transfer of genetic information from the DNA into the protein. AARS catalyse the attachment of amino acids to transfer RNAs and thereby establish the rules of the genetic code by virtue of matching the nucleotide triplet of the anticodon with i...

The ability to catalyse an electrode reaction via direct (mediatorless) electron transfer has been demonstrated for a number of redox enzymes. In the case of mediatorless electron transfer, the electron is transferred directly from the electrode to the substrate molecule via the active site of the enzyme, or vice versa. The electron itself is the second substrate for the reaction. An important ...

background: there is no doubt that luteal phase support is essential to enhance the reproductive outcome in ivf cycles. in addition to progesterone and human chorionic gonadotropin, several studies have described gnrh agonists as luteal phase support to improve implantation rate, pregnancy rate and live birth rate, whereas other studies showed dissimilar conclusions. all of these studies have b...

in this paper, the problem of turbulent forced convection flow of water- alumina nanofluid in a uniformly heated pipe has been thoroughly investigated. in numerical study, single and two-phase models have been used. in single-phase modeling of nanofluid, thermal and flow properties of nanofluid have been considered to be dependent on temperature and volume fraction. effects of volume fraction a...

heat transfer phenomena in batch fluidized bed dryer have been studied and analyzed using three phase model including solid phase, interstitial gas phase and bubble phase based on rizzi model. new correlations of heat transfer coefficient to surrounding and convection heat transfer coefficient between solid and interstitial gas are being proposed. in addition, some modifications have been done ...

Ir complexes of chiral phosphine-diamine ligands catalyse the hydrogenation and transfer hydrogenation of aryl-piperidin-4-yl methanones, and ketones bearing both an aryl group and secondary alkyl substituent with up to 98% e.e., and with substrate to catalyst ratios of up to 4000.

an experimental study of the phase inversion behavior of liquid-liquid dispersion has been conducted in a spray extraction column for systems of toluene / water, n-hexane/water, ccl4/water, toluene /water + glycerol (25 % wt), toluene + ccl4 (25 % wt) / water and toluene / acetic acid (5 % wt)/water. the effects of physical properties, mass transfer and column geometry on phase inversion have b...

Rabbit muscle phosphoglucomutase converts a-D-glucose 1_[(S)-160,17O,8Olphosphate into D-glucose 6-[160,'70,18Olphosphate, which is shown by 31P n.m.r. spectroscopy, after cyclization and methylation, to have the (S)-configuration at the phosphorus atom. Since phosphoglucomutase is known to catalyse phosphoryl transfer by way of a phospho-enzyme intermediate, and since individual phosphoryl-tra...

Computational methods have now become a valuable tool to understand the way in which enzymes catalyse chemical reactions and to aid the interpretation of a diverse set of experimental data. This study focuses on the influence of the condensed-phase environment structure on proton transfer mechanisms, with an aim to understand how C-H bond cleavage is mediated in enzymatic reactions. We shall us...

trifluoromethylated organic compounds, especially chiral quaternary alcohols bearing trifluoromethyl group are of important intermediates in drugs, agrochemicals and etc.an efficient epoxidation of β-cf3-β,β-disubstituted unsaturated ketones (6) has been developed with environmental benign hydrogen peroxide as the oxidant and f5-substituted chiral quaternary ammonium salt (1g or 5) derived from...