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Arbeloa Ernesto M - - 2010
The occurrence of mycosporine-like amino acids (MAAs) in the sea anemones Aulactinia marplatensis (Zamponi, 1977), Oulactis muscosa (Drayton in Dana, 1846) and Anthothoe chilensis (Lesson, 1830), from the rocky intertidal habitats on the coast of Mar del Plata, Argentina, was assessed by HPLC. The pattern of MAAs in the mussel ...
Neish Catherine D - - 2010
Titan organic haze analogues, or "tholins," produce biomolecules when hydrolyzed at low temperature over long timescales. By using a combination of high-resolution mass spectroscopy and tandem mass spectrometry fragmentation techniques, four amino acids were identified in a tholin sample that had been hydrolyzed in a 13 wt % ammonia-water solution ...
Hayami Yutaka - - 2010
Vertically aligned single-crystalline TiO2 rutile nanorod arrays were synthesized on FTO transparent conductive substrates, via the hydrolysis of TiCl4 under the co-existence of amino acid catalysts. Using TiO2 seed nanocrystals (prepared from Ti(IV) ethoxide, calcined at 450 degrees C for 1 h), TiO, rutile nanorod arrays grew at a relatively ...
Sivasundar Arjun - - 2010
Among various groups of fishes, a shift in peak wavelength sensitivity has been correlated with changes in their photic environments. The genus Sebastes is a radiation of marine fish species that inhabit a wide range of depths from intertidal to over 600 m. We examined 32 species of Sebastes for ...
Ji Zhi - - 2010
With density functional theory, vibrational circular dichroism (VCD) and infrared absorption (IR) spectra are obtained at the B3LYP/CC-pVTZ level of theory for 20 alpha-amino acids. The contribution of different vibration modes to the IR and VCD spectra is analyzed. Overall agreement between calculated results for amino acids in gas phase ...
Yan Lijun - - 2010
The mammalian target of rapamycin (mTOR) pathway is activated by a variety of stimuli, including nutrients such as glucose and amino acids. The Ste20 family kinase MAP4K3 is regulated by amino acids and acts upstream of mTORC1. Here we investigate how MAP4K3 activity is regulated by amino acid sufficiency. We ...
Rutledge Lesley R - - 2010
Previous computational studies have examined pi-pi and pi(+)-pi stacking and T-shaped interactions in nucleobase-amino acid dimers, yet it is important to investigate how additional amino acids affect these interactions since simultaneous contacts often appear in nature. Therefore, this paper investigates the geometries and binding strengths of amino acid-nucleobase-amino acid trimers, ...
Lansard Marine - - 2010
Amino acids are considered to be regulators of metabolism in several species, and increasing importance has been accorded to the role of amino acids as signalling molecules regulating protein synthesis through the activation of the TOR transduction pathway. Using rainbow trout hepatocytes, we examined the ability of amino acids to ...
LeDuc Stephen D - - 2010
Studies of soil nitrogen (N) availability over stand development have almost exclusively focused on mineral N, yet we increasingly recognize that plants can take up organic N in the form of free amino acids at biologically important rates. We investigated amino-acid and mineral N availability along a 10-site chronosequence of ...
Orcaray Luis - - 2010
BACKGROUND: The herbicide glyphosate inhibits the biosynthesis of aromatic amino acids by blocking the shikimate pathway. Imazethapyr and chlorsulfuron are two herbicides that act by inhibiting branched-chain amino acid biosynthesis. These herbicides stimulate secondary metabolism derived from the aromatic amino acids. The aim of this study was to test if ...
Sakauchi Satoshi - - 2010
The particular effect of 4 kinds of amino acid and peptide-rich food material (APRM) containing different charged amino acid contents on the gelatinization and retrogradation behavior of potato starch granules and on the water-vaporization behavior was analyzed by differential scanning calorimetry, rapid viscoanalysis, x-ray diffractometry, thermal gravimetry-differential thermal analysis, and ...
Kalra Seema - - 2010
This case report highlights the anaesthetic management of a patient who had residual muscle paralysis following neuromuscular blockade, which was attributed to hypothermia and corrected by administration of amino acid solution. The various causes of residual neuromuscular blockade should be considered when treating such a patient. Amino acid infusion has ...
Laska Matthias - - 2010
The olfactory properties of 6 amino acids were assessed in 20 human subjects using psychophysical tests of detectability, discriminability, and chemesthesis. Mean olfactory detection thresholds were found to be 10 microM for D-methionine, 80 microM for L-methionine, 200 microM for L-cysteine, 220 microM for D-cysteine, 75 mM for D-proline, and ...
Chaveroux Cédric - - 2010
In mammals, metabolic adaptations are required to cope with episodes of protein deprivation and malnutrition. Consequently, mammals have to adjust physiological functions involved in the adaptation to amino acid availability. Part of this regulation involves the modulation of the expression of numerous genes. In particular, it has been shown that ...
Callejón R M - - 2010
The amino acids present in foods and beverages affect the quality of these products and they play an important role in enology. Amino acids are consumed by yeasts as a source of nitrogen during alcoholic fermentation and are precursors of aroma compounds. In this review various chromatographic methodologies for the ...
Jende Inga - - 2010
Two-component systems usually function as cognate pairs, thereby ensuring an appropriate response to the detected signal. The ability to exclusively phosphorylate a partner protein, often in the presence of many competing homologous substrates, demonstrates a high level of specificity that must derive from the interacting surfaces of the two-component system. ...
Ogawa Kazuaki - - 2010
The present study investigates for the first time in any teleost the amino acid specificity and sensitivity of single glossopharyngeal (cranial nerve IX) fibers that innervate taste buds within the oropharyngeal cavity. These results are contrasted with similar data obtained from facial (cranial nerve VII) fibers that innervate extraoral taste ...
Zhang Chuanling - - 2010
Inorganic arsenic, an environmental contaminant, is known to cause cancer, developmental retardation, and many other serious diseases. Previous researches have shown that arsenic exerts its toxicity partially through generating reactive oxygen species (ROS). However, it is still not well understood how ROS links arsenic exposure to developmental retardation of preimplantation ...
Mitchell Robin E - - 2010
The four stereomers of 2-imino-3-methylene-5-L(carboxy-L-valyl)pyrrolidine, a bacterial metabolite that is inhibitory to the fire blight bacterium Erwinia amylovora, were synthesised and compared for antibacterial activity. Several alternative amino acid conjugates with L,L-stereochemistry were also prepared, and the synthesis was extended to 3-methylenepiperidine-6-L-carboxylic acid and a selection of 2-imino-3-methylenepiperidine-6-L-carboxy-L-amino acid conjugates. ...
Verbruggen Sascha - - 2010
BACKGROUND: Parenteral and enteral amino acid requirements for nutrition balance and function have not been defined in critically ill children or adults. In addition to playing a role in protein synthesis, amino acids trigger signaling cascades that regulate various aspects of fuel and energy metabolism and serve as precursors for ...
Bellec Aur?lien - - 2010
In the partial sublimation of three enantiomerically enriched amino acids, the ee of the sublimates can be explained by the ratio between the saturated vapor pressures of the racemate and the pure enantiomers.
Barton Michael D - - 2010
[This corrects the article on p. e11935 in vol. 5.].
Viglio Simona - - 2010
The continued publication from year to year of new MEKC formulations for the analysis of amino acids provides evidence that both CZE and MEKC still have a great power of attraction in this area. The present review intends to cover the literature on MEKC of amino acids from 2007 until ...
Liu Xiaoxia - - 2010
BACKGROUND: Even after years of exploration, the terrestrial origin of bio-molecules remains unsolved and controversial. Today, observation of amino acid composition in proteins has become an alternative way for a global understanding of the mystery encoded in whole genomes and seeking clues for the origin of amino acids. RESULTS: In ...
Diness Frederik - - 2010
A general method for synthesis of 1,4-substituted imidazolones from amino acids on solid support or in solution has been developed. Amino acid derived 3-Boc-(1,3)-oxazinane (Box) protected amino aldehyde building blocks were coupled through urea bonds to the amino terminal of dipeptides or amino acids. Upon acidic release, the aldehyde instantaneously ...
Cleaves H James HJ - - 2010
Biology uses essentially 20 amino acids for its coded protein enzymes, representing a very small subset of the structurally possible set. Most models of the origin of life suggest organisms developed from environmentally available organic compounds. A variety of amino acids are easily produced under conditions which were believed to ...
Shen Jerry - - 2010
The preferred amino acids in the proteolytic sites have been considered to be similar between caspase-1 and caspase-9, which do not support their differential functions in inflammatory pyroptosis and apoptosis. We attempted to solve this problem. We analyzed the flanking 20 amino acid residues in the cleavage sites in 34 ...
Marconi Anna Maria - - 2010
To determine the concentration of amino acids in women receiving the first course of antenatal betamethasone and to evaluate the umbilical venous and arterial amino acid concentrations at the time of elective cesarean section after betamethasone administration. Blood samples were collected from 34 pregnant women at risk of premature delivery ...
Kim Jeong-Ho - - 2009
Nutrient overload is associated with the development of obesity, insulin resistance, and type II diabetes. High plasma concentrations of amino acids have been found to correlate with insulin resistance. At the cellular level, excess amino acids impair insulin signaling, the mechanisms of which are not fully understood. Here, we report ...
Larsen Thomas - - 2009
Amino acids play an important role in ecology as essential nutrients for animals and as currencies in symbiotic associations. Here we present a new approach to tracing the origins of amino acids by identifying unique patterns of carbon isotope signatures generated by amino acid synthesis in plants, fungi, and bacteria ...
Abadir G B - - 2010
We study the interaction between short semi-metallic carbon nanotubes and different amino acids using molecular dynamics and ab initio (density functional theory/non-equilibrium Green's function) simulations. We identify two different mechanisms of nanotube conductance change upon adsorption of amino acids: one due to the change of the coordinates of the nanotube ...
Gottfries Johan - - 2010
A new set of amino acid descriptor scales was recently introduced. The new scales relate to amino acid side chain (i) rigidity and (ii) flexibility. These two properties were found to be orthogonal to each other. In this study, (i) the understanding of their meaning is improved, (ii) their utility ...
Wielemans Kevin - - 2010
When yeast cells detect external amino acids via their permease-like Ssy1 sensor, the cytosolic precursor forms of Stp1 and Stp2 transcription factors are activated by endoproteolytic removal of their N-terminal domains, a reaction catalyzed by the Ssy5 endoprotease. The processed Stp factors then migrate into the nucleus, where they activate ...
Yamamoto Yuzo - - 2009
We propose that amino acids in natal stream water have Important roles in Pacific salmon homing. This study hypothesized that amino acids found in natal stream water have a role in the ability of mature male chum salmon (Oncorhynchus keta) to home to the Osaru River (OR), Hokkaido, Japan. Behavioral ...
Rutherfurd Shane M - - 2009
Amino acid analysis is used to determine the amino acid content of amino acid-, peptide- and protein-containing samples. With minor exceptions, proteins are long linear polymers of amino acids connected to each other via peptide bonds. The first step of amino acid analysis involves hydrolyzing these peptide bonds. The liberated ...
Chaveroux Cédric - - 2009
It has been well established that amino acid availability can control gene expression. Previous studies have shown that amino acid depletion induces transcription of the ATF3 (activation transcription factor 3) gene through an amino acid response element (AARE) located in its promoter. This event requires phosphorylation of activating transcription factor ...
Yarus Michael - - 2009
By combining crystallographic and NMR structural data for RNA-bound amino acids within riboswitches, aptamers, and RNPs, chemical principles governing specific RNA interaction with amino acids can be deduced. Such principles, which we summarize in a "polar profile", are useful in explaining newly selected specific RNA binding sites for free amino ...
Lam Hubert - - 2009
In all known organisms, amino acids are predominantly thought to be synthesized and used as their L-enantiomers. Here, we found that bacteria produce diverse D-amino acids as well, which accumulate at millimolar concentrations in supernatants of stationary phase cultures. In Vibrio cholerae, a dedicated racemase produced D-Met and D-Leu, whereas ...
Dolensek Jurij - - 2010
In vivo investigations of catfish olfactory receptor neurons (ORNs) were previously limited to studying responses of spontaneously active cells. The olfactory organ, however, also contains ORNs that lack spontaneous activity and respond to amino acids. To record electrical activity of ORNs that were inactive prior to stimulation, we bathed the ...
Vardanega D - - 2009
Calculations of the interaction energy and dielectric responses of single-walled carbon nanotubes to the presence of amino acid inside (encapsulation) or outside (adsorption) the nanotube are carried out. It is shown that the frequency shifts of selected nanotubes conveniently tailored to the size of the probed molecules and used in ...
Chardwiriyapreecha Soracom - - 2009
Cu(2+)-treatment is a useful technique in selectively permeabilizing the fungal plasma membrane. We describe herein a practical application with Schizosaccharomyces pombe. Incubation of cells with 0.5 mM CuCl(2) at 30 degrees C for 20 min induced efficient leakage of cytosolic constituents. The kinetic characteristics of the calcium and amino acid ...
Voll Lars M - - 2009
Enolase catalyses the reversible conversion of 2-phosphoglycerate and phosphoenolpyruvate in glycolysis. Phosphoenolpyruvate constitutes an important branch point in plant metabolism. It is converted to pyruvate by pyruvate kinase and organic acids by phosphoenolpyruvate carboxylase. Phosphoenolpyruvate also acts as a precursor for the synthesis of aromatic amino acids in plastids. Tobacco ...
Yang Hong - - 2009
Improvement of culture media for mammalian cells is conducted via empirical adjustments, sometimes aided by statistical design methodologies. Here, we demonstrate a proof of principle for the use of constraints-based modeling to achieve enhanced performance of liver-specific functions of cultured hepatocytes during plasma exposure by adjusting amino acid supplementation and ...
Antonczak Alicja K - - 2009
The ability of Escherichia coli to grow on a series of acetylated and glycosylated compounds has been investigated. It is surmised that E. coli maintains low levels of nonspecific esterase activity. This observation may have ramifications for previous reports that relied on nonspecific esterases from E. coli to genetically encode ...
Hamase Kenji - - 2009
D-amino acids, the enantiomers of L-amino acids, are candidates to be novel physiologically active substances and the biomarkers in mammals. However, the amounts of D-amino acids in the tissues and physiological fluids are extremely small in most cases, and sensitive and selective analytical methods are needed for their determination. In ...
Krishtal Alisa - - 2009
The values of molecular polarizabilities and softnesses of the 20 amino acids were computed ab initio (MP2). By using the iterative Hirshfeld scheme to partition the molecular electronic properties, we demonstrate that the values of the softness of the side chain of the 20 amino acids are clustered in groups ...
Eschle B K - - 2009
T1R1/T1R3, taste-metabotropic glutamate receptor (mGluR) 4 and other taste receptors have been implicated in umami taste perceptionT1R1/T1R3 has also been identified as an L-amino acid receptor. We investigated the possibility that taste-mGluR4 receptors may also play a role in the taste of amino acids in Sprague-Dawley rats using conditioned taste ...
Scuderi D - - 2009
Gas-phase infrared spectra of deprotonated phosphorylated amino acids ([pAA-H](-))-phosphoserine ([pSer-H](-)), phosphothreonine ([pThr-H](-)), and phosphotyrosine ([pTyr-H](-))-and of the dihydrogen phosphate anion H(2)PO(4)(-) have been recorded in the mid-IR region (650-2000 cm(-1)) under tandem mass spectrometry conditions. The experimental setup involved a Paul ion trap equipped with an electrospray ionization source coupled ...
Araki Jun - - 2009
Novel polyrotaxane conjugates possessing side chains of protected amino acids, that is, N(α)-tert-butyloxycarbonylglycine (Boc-Gly) and N(α)-benzyloxycarbonylglycine (Z-Gly), were successfully prepared via the carbonyldiimidazole-mediated esterification of hydroxyl groups in a polyrotaxane. The prepared conjugates were soluble in a wide variety of organic solvents, including N,N-dimethylacetamide, N,N-dimethylformamide, tetrahydrofuran, pyridine, and methanol. Thermogravimetric ...
Hoang Cam Thuy - - 2009
A general strategy for the amino acid homologation via Blaise reaction and subsequent reduction is presented. This strategy involves the preparation of protected alpha-amino nitriles from the corresponding amino acids, followed by the zinc-mediated condensation of tert-butyl bromoacetate, to give the imidazolidones after iminozincate cyclization. Reduction gave the saturated imidazolidinones ...
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