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Barton Michael D - - 2010
Every protein has a biosynthetic cost to the cell based on the synthesis of its constituent amino acids. In order to optimise growth and reproduction, natural selection is expected, where possible, to favour the use of proteins whose constituents are cheaper to produce, as reduced biosynthetic cost may confer a ...
McDonald John H - - 2010
Whether particular amino acids are favored by selection at high temperatures over others has long been an open question in protein evolution. One way to approach this question is to compare homologous sites in proteins from one thermophile and a closely related mesophile; asymmetrical substitution patterns have been taken as ...
Wang Feng F Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California, United States of - - 2010
New tools are needed to study the intracellular pathogen Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), to facilitate new drug discovery and vaccine development. We have developed methodology to genetically incorporate unnatural amino acids into proteins in Mycobacterium smegmatis, BCG and Mtb, grown both extracellularly in culture and ...
Liu Bin B Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT 84602, - - 2010
Several chemokines have been shown to act as antimicrobial proteins, suggesting a direct contribution to innate immune protection. Based on the study of defensins and other antimicrobial peptides, it has been proposed that cationic amino acids in these proteins play a key role in their antimicrobial activity. The primary structure ...
Samsonov Sergey A - - 2009
Noncanonical amino acids with newly designed side-chain functionalities represent powerful tools to improve structural, biological, and pharmacological properties of peptides and proteins. In this context, fluorinated amino acids have increasingly gained importance. Despite the current wide use of fluorination in protein engineering, the basic properties of fluorine in protein environments ...
Huang Ying - - 2010
2-Amino-8-oxononanoic acid has been genetically incorporated into proteins in Escherichia coli by the use of an evolved pyrrolysyl-tRNA synthetase/pylT pair. The direct usage of the exclusive reactivity of the keto group in this amino acid with hydrazide- and alkoxyamine-bearing compounds to site-specifically label proteins under a mild condition close to ...
Nodet Gabrielle - - 2009
An atomic resolution characterization of the structural properties of unfolded proteins that explicitly invokes the highly dynamic nature of the unfolded state will be extremely important for the development of a quantitative understanding of the thermodynamic basis of protein folding and stability. Here we develop a novel approach using residual ...
Nasim S A - - 2009
Direct somatic embryo formation (without intervening callus) from garlic clove basal tissue was induced in which the influence of plant growth regulators (PGRs) on various explants was examined. Medium added with 2.0 mg/l 6-benzylaminopurine (BAP) and 0.5 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) were the most effective PGR combination for somatic embryo ...
Ruman Tomasz - - 2010
In search of an activity-preserving protein thiophosphorylation method, with thymidylate synthase recombinant protein used as a substrate, potassium thiophosphoramidate and diammonium thiophosphoramidate salts in Tris- and ammonium carbonate based buffer solutions were employed, proving to serve as a non-destructive environment. Using potassium phosphoramidate or diammonium thiophosphoramidate, a series of phosphorylated ...
Sagebakken Gry - - 2010
It is well known that many animals with placenta-like structures provide their embryos with nutrients and oxygen. However, we demonstrate here that nutrients can pass the other way, from embryos to the parent. The study was done on a pipefish, Syngnathus typhle, in which males brood fertilized eggs in a ...
Sullivan Michael L - - 2010
Red clover (Trifolium pratense) leaves accumulate several mumol of phaselic acid [2-O-caffeoyl-L-malate] per gram fresh weight. Post-harvest oxidation of such o-diphenols to o-quinones by endogenous polyphenol oxidases (PPO) prevents breakdown of forage protein during storage. Forages like alfalfa (Medicago sativa) lack both foliar PPO activity and o-diphenols. Consequently, breakdown of ...
H??gy P - - 2009
Spring wheat (Triticum aestivum L. cv. TRISO) was grown for three consecutive seasons in a free-air carbon dioxide (CO(2)) enrichment (FACE) field experiment in order to examine the effects on crop yield and grain quality. CO(2) enrichment promoted aboveground biomass (+11.8%) and grain yield (+10.4%). However, adverse effects were predominantly ...
Kleiger Gary - - 2009
Ubiquitin ligases, together with their cognate ubiquitin-conjugating enzymes, are responsible for the ubiquitylation of proteins, a process that regulates a myriad of eukaryotic cellular functions. The first cullin-RING ligase discovered, yeast SCF(Cdc4), functions with the conjugating enzyme Cdc34 to regulate the cell cycle. Cdc34 orthologs are notable for their highly ...
Riebeseel Erik - - 2010
Heterotrophic plastids of seeds perform many biosynthetic reactions. Understanding their function in crop plants is crucial for seed production. Physiological functions depend on the uptake of precursors by a range of different metabolite translocators. The 2-oxoglutarate/malate translocator gene (PsOMT), which is highly expressed during pea (Pisum sativum) embryo maturation, has ...
Fregolente Patricia B L - - 2009
Gamma linolenic acid (GLA, 18:3, cis- 6,9,12- octadecatrienoic acid), an important compound in n- 6 eicosanoid family biosynthesis, occurs in the lipids of a few plant and microbial sources. This study focused on the screening of microbial strains with suitable lipase activity for enrichment of GLA by selective hydrolysis of ...
Kilberg Michael S - - 2009
Mammals respond to dietary nutrient fluctuations; for example, deficiency of dietary protein or an imbalance of essential amino acids activates an amino acid response (AAR) signal transduction pathway, consisting of detection of uncharged tRNA by the GCN2 kinase, eIF2alpha phosphorylation and ATF4 expression. In concert with heterodimerization partners, ATF4 activates ...
Miyamoto Tetsuya - - 2010
It has long been believed that amino acids comprising proteins of all living organisms are only of the L-configuration, except for Gly. However, peptidyl D-amino acids were observed in hydrolysates of soluble high molecular weight fractions extracted from cells or tissues of various organisms. This strongly suggests that significant amounts ...
Millington Keith R - - 2010
Chemiluminescence (CL) with maximum emission in the range 550-650 nm is observed when proteins and certain amino acids are heated in air, and CL intensity is significantly reduced in nitrogen. Of the 20 common amino acids, lysine (Lys) has the highest thermal CL intensity by a factor of approximately 30 ...
Jamal Shazia - - 2009
We report the effects of stabilizing osmolytes (low molecular mass organic compounds that raise the midpoint of thermal denaturation) on the stability and function of RNase-A under physiological conditions (pH 6.0 and 25 degrees C). Measurements of Gibbs free energy change at 25 degrees C (DeltaG(D) degrees ) and kinetic ...
Voloshchuk Natalya - - 2010
The challenge of synthetic biology lies in the construction of artificial cellular systems. This requires the development of modular "parts" that can be integrated into living systems to elicit an artificial, yet programmed, response or function. The development of methods to engineer proteins bearing unnatural amino acids (UAAs) provides essential ...
Chinta Jugun Prakash - - 2009
A lower rim naphthylidene conjugate of calix[4]arene [L] has been synthesized and characterized, and the structure has been established on the basis of single crystal XRD. The L has been found to be selective toward Zn(2+), which induces appropriate changes in the arms of L so that the N(2)O(2) coordination ...
Farnfield Michelle M - - 2009
Background and objectives The digestion rate of proteins and subsequent absorption of amino acids can independently modulate protein metabolism. The objective of the present study was to examine the blood amino acid response to whey protein isolate (WPI), β-lactoglobulin-enriched WPI, hydrolysed WPI and a flavour-identical control. Methods Eight healthy adults ...
Churchill Cassandra D M - - 2009
The pi-pi stacking (face-to-face) interactions between the five natural DNA or RNA nucleobases and the four aromatic amino acids were compared using three different types of dimers: (1) a truncated nucleoside (nucleobase) stacked with a truncated amino acid; (2) a truncated nucleoside (nucleobase) stacked with an extended amino acid; and ...
Catalfo Alfio - - 2009
The aromatic amino acid tryptophan is the most susceptible protein residue involved in various photosensitized adverse effects. Of these processes, the tryptophan photosensitization induced by methylene blue has been well studied. A predominant type II photosensitizing activity, mediated by singlet oxygen, has been already demonstrated on various models. The purpose ...
Jones David H - - 2010
A large number of amino acids other than the canonical amino acids can now be easily incorporated in vivo into proteins at genetically encoded positions. The technology requires an orthogonal tRNA/aminoacyl-tRNA synthetase pair specific for the unnatural amino acid that is added to the media while a TAG amber or ...
Salwiczek Mario - - 2009
Systematic model investigations of the molecular interactions of fluorinated amino acids within native protein environments substantially improve our understanding of the unique properties of these building blocks. A rationally designed heterodimeric coiled coil peptide (VPE/VPK) and nine variants containing amino acids with variable fluorine content in either position a16 or ...
Panza Víctor - - 2009
Comparative studies on fatty acid and protein composition of the endosperm and embryo of palmito (Euterpe edulis Martius) were conducted using gas-liquid chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. On a dry weight basis, the embryo contained extremely lower amounts of lipids and proteins than did the endosperm, which was ...
Dovidchenko N V - - 2009
We have investigated the possibility to predict protection of amino acid residues from hydrogen-deuterium exchange. A database containing experimental hydrogen-deuterium exchange data for 14 proteins for which these data are known has been compiled. Different structural parameters related to flexibility of amino acid residues and their amide groups have been ...
Tomé Daniel - - 2009
Dietary protein and amino acids, including glutamate, generate signals involved in the control of gastric and intestinal motility, pancreatic secretion, and food intake. They include postprandial meal-induced visceral and metabolic signals and associated nutrients (eg, amino acids and glucose), gut neuropeptides, and hormonal signals. Protein reduces gastric motility and stimulates ...
Shozen Naoki - - 2009
Site-directed incorporation of PEGylated nonnatural amino acids with 4, 8, and 12 repeated ethylene glycol units was examined in a cell-free translation system. PEGylated aminophenylalanine derivatives were successfully incorporated into proteins, whereas PEGylated lysines were not. The incorporation efficiency of the PEGylated amino acids decreased with an increase in PEG ...
Rittler Peter - - 2009
BACKGROUND: Currently, it is unknown whether recommended rates of amino acid infusion are sufficient to support hepatic or intestinal protein synthesis specifically after operation. The objective of the study was to determine the effect of a standard parenteral amino acid dose on serum albumin and ileum protein synthetic rates in ...
Randi?? M - - 2009
We consider a spectrum-like two-dimensional graphical representation of proteins based on a reduced protein model in which 20 amino acids are grouped into five classes. This particular grouping of amino acids was suggested by Riddle and co-workers in 1997. The graphical representation is based on depicting sequentially the amino acids ...
de Graaf Albert J - - 2009
Over the years, several chemical reactions have been developed that enable the covalent conjugation of synthetic molecules to natural proteins. The resulting bioconjugates have become important tools in the study of natural proteins. Furthermore, they form a new class of protein-based pharmaceuticals and biomaterials. However, classical bioconjugation reactions to natural ...
Das Piyali - - 2009
This study evaluated the extent of oxidative stress by measuring malondialdehyde and ascorbic acid in the seminal plasma of human subjects with different fertility potential. Semen samples from 148 subjects were evaluated (48 normozoospermics, 34 oligoasthenoteratozoospermics, 34 asthenoteratozoospermics and 32 azoospermics). malondialdehyde level was found to be significantly higher in ...
Liu Yangsheng - - 2009
This study developed a novel technology for sewage sludge utilization. The bacteria proteins in the sewage sludge were extracted to produce the amino acid chelated trace elements (AACTE) fertilizer by virtue of several chemical processes. Firstly, the sewage sludge was hydrolyzed under hot hydrochloric acid solution to obtain protein solution. ...
Higgs Paul G - - 2009
Of the 20 amino acids used in proteins, 10 were formed in Miller's atmospheric discharge experiments. The two other major proposed sources of prebiotic amino acid synthesis include formation in hydrothermal vents and delivery to Earth via meteorites. We combine observational and experimental data of amino acid frequencies formed by ...
Georgiev Alexander G - - 2009
Informative numerical representations of amino acid residues are essential for successful in silico modeling or establishing the structure-activity relationships of proteins. A straightforward approach is adopted here for representing more than 500 amino acid indices from the AAindex database by a set of uncorrelated scales, satisfying the varimax criterion. Different ...
Zuo Yong-Chun - - 2010
Due to the complexity of Plasmodium falciparumis genome, predicting secretory proteins of P. falciparum is more difficult than other species. In this study, based on the measure of diversity definition, a new K-nearest neighbor method, K-minimum increment of diversity (K-MID), is introduced to predict secretory proteins. The prediction performance of ...
de Bivort Benjamin L - - 2009
The metabolic cycle of Saccharomyces cerevisiae consists of alternating oxidative (respiration) and reductive (glycolysis) energy-yielding reactions. The intracellular concentrations of amino acid precursors generated by these reactions oscillate accordingly, attaining maximal concentration during the middle of their respective yeast metabolic cycle phases. Typically, the amino acids themselves are most abundant ...
Kim Eunjung - - 2009
Amino acids are key nutrients for protein synthesis and many metabolic processes. There is compelling evidence that amino acids themselves regulate protein synthesis, degradation and cell growth. Mammalian target of rapamycin complex 1 (mTORC1) plays a central role in cellular growth regulation. Amino acids potently activate mTORC1, however, the mechanism ...
Umemoto Hirohito - - 2009
Xylanase J (XynJ) from alkaliphilic Bacillus sp. 41M-1 is an alkaline xylanase. The crystal structure has been solved with XynJ. Improvement of the alkaliphily of XynJ was attempted by amino acid substitutions. Reinforcing the characteristic salt bridge in the catalytic cleft and introducing excess Arg residues on the protein surface ...
Sanders Ann - - 2009
The embryo of Arabidopsis seeds is symplasmically isolated from the surrounding seed coat and endosperm, and uptake of nutrients from the seed apoplast is required for embryo growth and storage reserve accumulation. With the aim of understanding the importance of nitrogen (N) uptake into developing embryos, we analysed two mutants ...
Mansoori B - - 2009
1. A precision feeding experiment was conducted to evaluate the effects of tannic acid (TA) and polyethylene glycol (PEG) on the excretion of amino acids, and the apparent and true digestibility of gelatin protein in broilers. 2. In a 3 x 2 x 2 factorial design, ninety-six 7-week-old broiler cockerels ...
Carmo-Silva Ana E AE Centro de Engenharia Biológica and Departamento de Biologia Vegetal, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal. - - 2009
Plants produce various compounds in response to water deficit. Here, the presence and identification of a drought-inducible non-protein amino acid in the leaves of two C(4) grasses is first reported. The soluble amino acids extracted from the leaves of three different species were measured by high-performance liquid chromatography of derivatives ...
Sohn Sung-Hwa - - 2009
The endoplasmic reticulum (ER) is a principal site for protein synthesis, protein folding, calcium storage, and calcium signaling. Thapsigargin (TG), an inducer of ER stress, inhibits ER-associated Ca(2+)-ATPase and disrupts Ca(2+) homeostasis. ER stress plays an important pathogenetic role in Alzheimer's disease, Parkinson's disease, Huntington's disease, Lou Gehrig's disease, and ...
Ajayi O B - - 2009
The seed of Kerstingiella geocarpa was analyzed to determine its proximate and amino acid compositions. The seed was found to be a high source of crude protein (21.3%) and very low in crude fat (1.0%). Arginine, an amino acid for pediatric growth, was the most concentrated amino acid in the ...
Sun Cheng Jun - - 2009
The sandcastle worm Phragmatopoma californica, a marine polychaete, constructs a tube-like shelter by cementing together sand grains using a glue secreted from the building organ in its thorax. The glue is a mixture of post-translationally modified proteins, notably the cement proteins Pc-1 and Pc-2 with the amino acid, 3,4-dihydroxyphenyl-L-alanine (DOPA). ...
Gao Qing-Bin - - 2009
Nuclear receptors are involved in multiple cellular signaling pathways that affect and regulate processes such as organ development and maintenance, ion transport, homeostasis, and apoptosis. In this article, an optimal pseudo amino acid composition based on physicochemical characters of amino acids is suggested to represent proteins for predicting the subfamilies ...
Poosuwan K - - 2010
The objective of this study was to determine the effect of protein levels on production performance, immune response, liver triglyceride and plasma amino acids profile of laying hens during 21-48 weeks of age. Two groups of commercial hens (Babcock B-308) were fed with diets with different crude protein levels (14% ...
Ohta Akio - - 2009
The incorporation behaviors of some N-dodecanoyl amino acid-type surfactants into L-alpha-dipalmitoylphosphatidylcholine (DPPC) vesicles in aqueous solution were investigated. From the leakage measurements of a vesicle-entrapped fluorescence probe, it was found that these surfactants did not affect the DPPC vesicle so much at a very low concentration less than a one-tenth ...
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