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Chelliah V - - 2005
One of Oleg Ptitsyn's most important papers (Shakhnovich, E., Abkevich, V., and Ptitsyn, O. (1996) Nature, 379, 96-98) describes how knowledge of structure and function can be used to understand better the nature of amino acid substitutions in families and superfamilies of proteins. The selective advantages of retaining structure and ...
Braun Phyllis C - - 2005
Farnesol, a quorum sensing (QS) signal, is produced by Candida albicans during high density growth and has been found to inhibit morphogenesis. This QS auto-inducing signal was discovered to increase amino acid incorporation by C. albicans when concentrations of farnesol increased to 10 microg/mL in yeast nitrogen broth. Farnesol concentrations ...
Lian P Z - - 2005
The squid (Loligo pealei) byproduct composed of heads, viscera, skin, fins, and small tubes was subjected to hydrolysis at 55 degrees C and natural pH (6.8) using endogenous proteases. Squid hydrolysate was characterized during the course of hydrolysis for changes in the degree of hydrolysis, viscosity, electrophoretic pattern of proteins ...
Rittler Peter - - 2005
BACKGROUND: Amino acids are an integral part of parenteral nutrition because of their anabolic action helping to conserve body protein after surgical stress. At the gastrointestinal tract, an adequate supply of amino acids may be particularly important because of the gut's high rate of protein turnover, cell division, and proliferation. ...
Banerjee T - - 2005
Correlations between genomic GC contents and amino acid frequencies were studied in the homologous sequences of 12 eubacterial genomes. Results show that amino acids encoded by GC-rich codons increases significantly with genomic GC contents, whereas opposite trend was observed in case of amino acids encoded by GC-poor codons. Further studies ...
Wu Guang - - 2005
In this study, we analyze the amino acid pairs in human protein C precursor to determine which amino acid pairs are more susceptible to 71 variants from missense mutant human protein C precursor. The results show 85.92% of 71 variants occur at randomly unpredictable amino acid pairs accounting for 61.96% ...
Yampolsky Lev Y - - 2005
The comparative analysis of protein sequences depends crucially on measures of amino acid similarity or distance. Many such measures exist, yet it is not known how well these measures reflect the operational exchangeability of amino acids in proteins, since most are derived by methods that confound a variety of effects, ...
Hamada Hiroyuki - - 2005
A new fluorescent amino acid, L-2-acridonylalanine, was incorporated into proteins at specific positions using 4-base codon/anticodon strategy. The efficiency of the incorporation was high enough to obtain enough quantities of the mutants. The acridonyl group was highly fluorescent when it was excited at the wavelengths of blue-lasers and was highly ...
Aziz Alfred - - 2005
Protein ingestion after injection of the glucagon-like peptide-1 receptor agonist Exendin-4 (Ex-4) causes hyperglycemia in rats. The objectives of this study were to determine the components of protein digestion responsible for this effect and to associate it with changes in the concentrations of other metabolites and hormones. Two experiments were ...
Leukert Nadja - - 2005
S100 proteins form characteristic homo- and/or heterodimers that play a role in calcium-mediated signaling. We characterized the formation of the human S100A8/S100A9 heterodimer using the yeast two-hybrid system. Employing site-directed mutagenesis we found that distinct hydrophobic amino acids of helix I/I' are located at a crucial site of the S100A8/S100A9 ...
Moughan Paul J - - 2005
When a food is processed or stored, amino acids can react with a number of chemical entities to produce new compounds that are often nutritionally unavailable to the consumer. During acid hydrolysis used in amino acid analysis, some of these compounds revert back to the parent amino acid, leading to ...
Teixeira Miguel C - - 2005
The intensive use of herbicides may give rise to a number of toxicological problems in non-target organisms and has led to the emergence of resistant weeds. To gain insights into the mechanisms of adaptation to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), we have identified variations in protein expression level in the ...
Darragh Alison J - - 2005
Determining the amino acid content of a protein involves the hydrolysis of that protein, usually in acid, until the protein-bound amino acids are released and made available for detection. Both the variability in the ease of peptide bond cleavage and differences in the acid stability of certain amino acids can ...
Peace Robert W - - 2005
Amino acids in foods exist in a free form or bound in peptides, proteins, or nonpeptide bonded polymers. Naturally occurring L-amino acids are required for protein synthesis and are precursors for essential molecules, such as co-enzymes and nucleic acids. Nonprotein amino acids may also occur in animal tissues as metabolic ...
De La Barca Ana María Calderón - - 2005
Two ultrafiltered soy flour protein fractions were evaluated; the first was obtained by hydrolysis (0.5-3 kDa, F(0.5-3)), and the second was an enzymatically methionine-enriched fraction (1-10 kDa, F(1-10)E). Amino acid profiles, protein quality, allergenicity (against soy-sensitive infant sera) and trypsin inhibitor activity were determined. Fraction F(1-10)E fulfilled amino acid requirements ...
Li Ying - - 2005
The stability of the isolated C-terminal domain of the ribosomal protein L9 (CTL9) is strongly dependent upon pH. Below pH 4.2, the folded and unfolded states are both populated significantly. Their interconversion is slow on the NMR chemical shift time-scale and separate, well-resolved resonances from each state are observed. This ...
Pacholczyk Marcin - - 2005
In this paper, a new algorithm is presented, which makes possible multilevel comparison of BLOSUM protein substitution matrices based on data from different groups of organisms. As an example, a comparison between substitution matrices based on data from two groups of bacterial genomes with different GC content is presented. Our ...
Tuttle Katherine R - - 2005
BACKGROUND: In diabetes, high intake of dietary protein exacerbates responses associated with kidney damage. Increased levels of amino acids could injure cells by providing free amino groups for glycation reactions leading to advanced glycation end products (AGEs). METHODS: Rat mesangial cells were cultured with increased amino acids designed to resemble ...
Lim Victoria S - - 2005
Hemodialysis (HD) is a protein catabolic procedure. Whole-body amino acid turnover studies identify dialysate amino acid loss and reduced protein synthesis as the catabolic events; proteolysis is not increased. Regional amino acid kinetics, however, document enhanced muscle protein breakdown as the cause of the catabolism; muscle protein synthesis also increased ...
Jordan I King - - 2005
Amino acid composition of proteins varies substantially between taxa and, thus, can evolve. For example, proteins from organisms with (G + C)-rich (or (A + T)-rich) genomes contain more (or fewer) amino acids encoded by (G + C)-rich codons. However, no universal trends in ongoing changes of amino acid frequencies ...
Ayodeji O. Fasuyi
Cassava leaf samples harvested from local and genetically improved cassava varieties were processed into cassava leaf meal (CLM) and cassava leaf protein concentrate (CLPC) using the low cost village-level fractionation scheme. Chemical and physicochemical analyses were carried out to determine the proximate and amino acids composition and to also ascertain ...
Ferrando Arny A - - 2005
This review discusses the concept that skeletal muscle intracellular amino acids (ICAAs), in particular the essential amino acids, are regulated throughout a wide range of physiologic circumstances. Whether in critical illness, severe injury, or healthy states, ICAAs are closely regulated by a coordinated response in 1 or more of the ...
Adam Petra - - 2005
BACKGROUND: Insect cells can serve as host systems for the recombinant expression of eukaryotic proteins. Using this platform, the controlled expression of 15N/13C labelled proteins requires the analysis of incorporation paths and rates of isotope-labelled precursors present in the medium into amino acids. For this purpose, Spodoptera frugiperda cells were ...
Tian Hong Er - - 2005
The contents of amino acids and proteins and the activity of Na+,K+-ATPase were determined in roots, stems, and leaves of Eu3+-treated Lathyrus sativus L. The results showed that the treatment of Eu3+ made the contents of amino acid and protein and the activity of Na+,K+-ATPase change. The first possible mechanism ...
Dasgupta Mou - - 2005
Adequate dietary intakes of all indispensable amino acids are vital to optimal health. Using three random 24-hour dietary recalls and the newly released Dietary Reference Intakes (DRIs), we examined the extent and correlates of inadequate dietary intakes of indispensable amino acids among 323 homebound older adults who received home-delivered meals. ...
Chaudhuri Barnali N - - 2005
In several natural settings, the standard genetic code is expanded to incorporate two additional amino acids with distinct functionality, selenocysteine and pyrrolysine. These rare amino acids can be overlooked inadvertently, however, as they arise by recoding at certain stop codons. We report a method for such recoding prediction from genomic ...
Adebiyi Abayomi Peter - - 2005
The acid hydrolysis of proteins was miniaturized and simplified by employing microcapillary tubes (100 microl in volume) with 6 M HCl containing 1% 2-mercaptoethanol and 3% phenol for an amino acid compositional analysis. The method not only eliminated the laborious evacuation step for the hydrolysis tube but also decreased the ...
Cuthbertson Daniel - - 2005
The nature of the deficit underlying age-related muscle wasting remains controversial. To test whether it could be due to a poor anabolic response to dietary amino acids, we measured the rates of myofibrillar and sarcoplasmic muscle protein synthesis (MPS) in 44 healthy young and old men, of similar body build, ...
Benedict Christian - - 2005
The enhanced cortisol release after protein-rich meals might represent a neuroendocrine response to food allergens. We tested whether the antigenicity of proteins contributes to this effect. Twelve healthy men nasogastrically received casein, its less allergenic hydrolysate, and placebo. Contrary to expectations, secretion of cortisol (area under the curve, 742.70 +/- ...
Cropp T Ashton - - 2004
More than 30 novel amino acids have been genetically encoded in response to unique triplet and quadruplet codons including fluorescent, photoreactive and redox active amino acids, glycosylated and heavy atom derived amino acids in addition to those with keto, azido and acetylenic chains. In this article, we describe recent advances ...
Sugimoto Megumi - - 2004
The hypersensitive response (HR) is one of the most critical defense systems in higher plants. In order to understand its molecular basis, we have screened tobacco genes that are transcriptionally activated during the early stage of the HR by the differential display method. Among six genes initially identified, one was ...
Jinn Tsung-Luo - - 2004
Accumulation of class I small heat shock proteins (sHSPs) is induced by the proline analog, azetidine-2-carboxylic acid (Aze) in soybean seedlings to a level similar to that induced by exposure to 40 degrees C. However, only the treatment with 10 mM Aze for 6 h and subsequently with 10 mM ...
van Gammeren A J - - 2004
Partly biosynthetic site-directed isotopically (13)C enriched photosynthetic light-harvesting 2(LH2) complexes have been prepared from Rhodopseudomonas acidophila strain 10050 by using chemically labeled [1,2,3,4-(13)C], [1,4-(13)C] and [2,3-(13)C] succinic acid as a precursor in the growth medium. Two-dimensional proton driven spin diffusion (PDSD) solid state NMR correlation spectroscopy has been used to ...
Hinault Charlotte - - 2004
Amino acids are nutrients responsible for mammalian target of rapamycin (mTOR) regulation in mammalian cells. The mTOR protein is mainly known for its role in regulating cell growth, notably via protein synthesis. In addition to amino acids, mTOR is regulated by insulin via a phosphatidylinositol 3-kinase (PI 3-kinase)-dependent pathway. mTOR ...
Coye Lisette H - - 2004
Streptococcus pyogenes, the aetiological agent of both respiratory and skin infections, produces numerous exotoxins to establish infection. This report identifies a new exotoxin produced by this organism, termed SpyA, for S. pyogenesADP-ribosylating toxin. SpyA, MW 24.9, has amino acid identity with the ADP-riboslytransferases (ADPRTs) Staphylococcus aureus EDIN and Clostridium botulinum ...
Ronchi Virginia Paola - - 2004
The contents of glutathione S-transferase (GST) subunits, carbonic anhydrase III (CAIII), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and a 230 kDa protein are affected by protein deprivation in mouse liver. In order to know if particular amino acids control these contents, the effects of feeding for 5 days with diets containing different amino ...
Salerno C - - 2004
An homology model of human adenylosuccinate lyase structure shows that P100A substitution distorts the amino acid chain of domain I in the proximity of His-86, which behaves as general acid in the catalysis, and may expose Cys-98 and Cys-99 to oxidising agents. This model is in line with the observation ...
Van Melckebeke Hélène - - 2004
A detailed theoretical and experimental analysis of the artifacts induced by homonuclear band-selective decoupling during CT frequency labeling is presented. The effects are discussed in the context of an amino-acid-type editing filter implemented in (1)H-(13)C CT-HSQC experiments of methyl groups in proteins. It is shown that both Bloch-Siegert shifts and ...
Maheshwari R - - 2004
It is of great interest and importance to study how different amino acid residues contribute to and affect the properties of proteins coated as films on solid surface. This work shows that the solid/liquid interfacial energy of surface localized amino acid films and their Gibbs energies of transfer at the ...
Stevens Anthony - - 2004
The specificity determinants for susceptibility to resistance by the Fv1 n and b alleles map to amino acid 110 of the murine leukemia virus CA protein. To study the interaction between Fv1 and CA, we examined changes in CA resulting in the loss of susceptibility to Fv1 resistance in naturally ...
Lougheed Tyler - - 2004
Incorporation of photo-switchable amino acids into peptides and proteins offers prospects for the control of complex biochemical processes using light. Currently, only a few photo-switchable amino acids are known. We report the design and synthesis of a novel hemithioindigo-based amino acid and its incorporation into the model ion channel gramicidin. ...
Pack Seung Pil - - 2004
Structural distributions of each amino acid were compared between 20 pairs of thermophilic and mesophilic proteins to obtain thermostable factors. Five kinds of residual structure states such as fully-exposed, exposed, partially exposed (or partially buried), buried, well-buried states were considered for analyzing the structural patterns of amino acids. The statistical ...
Fatufe A A - - 2004
Male chickens of a broiler (B) and a layer (L) genotype were grown in floor pens from d 8 to 21 posthatch in groups of 10. Three pens per genotype were allocated to each of 10 experimental diets. The diets were offered ad libitum and they differed in lysine concentration ...
Jacob Claus - - 2004
Recent studies on the redox behaviour of cysteine residues in peptides and proteins have dramatically changed our perspective of the amino acid's role in biocatalysis, intracellular redox sensing and cell signalling. Cysteine sulfinic acid formation in proteins, for example, has long been viewed as an irreversible 'overoxidation' process that might ...
Gibney Michael J - - 2004
Although the amino acid composition of almost all food proteins is known, estimating the amino acid intake from the diet is extremely difficult because of the lack of available data. A conservative approach would be to determine the population distribution of protein intake, select the 97.5(th) or higher percentile of ...
Baracos Vickie E - - 2004
One important advantage of animal models is that they permit invasive approaches and can be especially valuable when evaluating tissue and specific features of metabolism in situ. The focus of this presentation is current models, which are providing insights into the pivotal importance of the gastrointestinal tract in amino acid ...
Soeters Peter B - - 2004
Amino acid utilization and, therefore, demand differ between the healthy state and various disease states. In the healthy state most circulating amino acids are derived from dietary proteins that are stored and broken down in the gut and released gradually into the portal circulation, and from continuous turnover of body ...
Orita Yoshimasa - - 2004
BACKGROUND: It has been reported that an acute load of beefsteak (200 g) significantly enhanced the glomerular filtration rate (GFR; inulin clearance and creatinine clearance) in healthy human subjects compared to that in the same subjects in the fasted state. However, no comparative study of the effects of the same ...
Tang Hua - - 2004
Different nonsynonymous changes may be under different selective pressure during evolution. Of the 190 possible interchanges among the 20 amino acids, only 75 can be attained by a single-base substitution. An evolutionary index (EI) can be empirically computed for each of the 75 elementary changes as the likelihood of substitutions, ...
Lichtenecker Roman - - 2004
A novel method is proposed for the analysis of protein NOEs in solution. In this approach, chemically synthesized precursor compounds for the amino acids valine, leucine, and isoleucine are used for amino acid specific labeling of these hydrophobic residues. The methodology is based on a novel synthetic route to 12C,1H,2H ...
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