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Tajima Shigeyuki - - 2004
In tropical legumes like Glycine, Phaseolus and Vigna sp., ammonia as direct product of symbiotic nitrogen fixation is converted to ureides (allantoin and allantoic acid) and they were translocated to the shoots as nitrogen source. In the xylem sap of soybean in reproductive phase the ureides reached to 60-75% of ...
Tsui T K N - - 2004
The oriental weatherloach Misgurnus anguillicaudatus is an extremely ammonia-tolerant fish. Many ammonia-protection mechanisms have been reported in this fish. Six strategies used by this fish to deal with the problem of excess ammonia are described. The fish can (1) reduce ammonia production through reduction in protein and/or amino acid catabolism; ...
Mullins Irene M - - 2004
The deduced amino acid variability for the 10 kDa prolamin was determined for 16 Oryza species, both cultivated (rice) and wild. Prolamin, a seed storage protein and site of nitrogen and sulfur accumulation, is sequestered in the subaleurone layer of the starchy endosperm for use during seedling germination. The 10 ...
Veeneman Jorden M - - 2004
BACKGROUND: The PNA (protein equivalent of nitrogen appearance) is used to calculate protein intake from urea kinetics. One of the essential assumptions in the calculation of PNA is that urea accumulation in haemodialysis (HD) patients is equivalent to amino acid oxidation. However, urea is hydrolysed in the intestine and the ...
Abdel-Sater Fadi - - 2004
Yeast cells respond to the presence of amino acids in their environment by inducing transcription of several amino acid permease genes including AGP1, BAP2, and BAP3. The signaling pathway responsible for this induction involves Ssy1, a permease-like sensor of external amino acids, and culminates with proteolytic cleavage and translocation to ...
McCuistion K C - - 2004
Two experiments were conducted with ruminally cannulated Holstein steers to determine effects of N supply on histidine (His) utilization. All steers received 2.5 kg DM/d of a diet based on soybean hulls; abomasal infusion of 250 g/d amino acids, which supplied adequate amounts of all essential amino acids except His; ...
Ramírez-Silva Ma Teresa - - 2004
Acidity constants for the 5-amino-1,10-phenanthroline (5-Aphen) were determined in aqueous media, using SQUAD and SUPERQUAD programs. Spectrophotometry and potentiometry data were fitted to the best model to enable correlation of the following acidity equilibria: 5-AphenH = 5-Aphen + H+ (-log K = 5.78 +/= 0.03) and 5-AphenH2 = 5-AphenH2 = ...
Cha Jae-Young - - 2004
The influence of feedstock amino acids, salt, carbon and nitrogen sources on glutathione production by Saccharomyces cerevisiae FF-8 was investigated. Glucose, yeast extract, KH2PO4, and L-cysteine were found to be suitable feedstock. Highest glutathione production was obtained after cultivation with shaking for 72 h in a medium containing glucose 3.0% ...
Beltran Gemma - - 2004
We carried out fermentations with several nitrogen sources in different concentrations and studied nitrogen regulation by following the transcriptional profile of the general amino-acid permease (GAP1) and the ammonium permeases (MEP1, MEP2, MEP3). In wine fermentations the cells evolve from a nitrogen-repressed situation at the beginning of the process to ...
Zubavichus Yan - - 2004
Decomposition of five amino acids, alanine, serine, cysteine, aspartic acid, and asparagine, under irradiation with soft X rays (magnesium Kalpha X-ray source) in ultra-high vacuum was studied by means of X-ray photoelectron spectrometry (XPS) and mass spectrometry. A comparative analysis of changes in XPS line shapes, stoichiometry and residual gas ...
Andréasson Claes - - 2004
We have found that proline and the toxic proline analogue azetidine-2-carboxylate (AzC) are efficiently imported into Saccharomyces cerevisiae cells by four amino acid permeases, including two nitrogen-regulated permeases (PUT4 and GAP1) and two permeases that are regulated by the SPS sensor of extracellular amino acids (AGP1 and GNP1). In contrast ...
Schreve James L - - 2004
The gene AGP2 and the ORF YFL055w (here named AGP3) are classified as members of the yeast amino acid permease gene family. Analysis of the growth of multiply-mutant strains in which these genes are disrupted shows that both encode permeases capable of supplying branched chain, and other, amino acids as ...
Moriwaki Hisataka - - 2004
Protein-energy malnutrition (PEM) is a common manifestation in cirrhotic patients with reported incidences as high as 65-90%. PEM affects largely the patients' quality of life and survival. Thus, diagnosis of and intervention for PEM is important in the clinical management of liver cirrhosis. Supplementation with branched-chain amino acids (BCAA) is ...
Kim B U - - 2004
Precipitation of ammonium together with phosphate and magnesium is a possible alternative for lowering the nitrogen content of wastewater. In this study we examine the removal of ammonium nitrogen and phosphorus from slurry-type swine wastewater containing high concentrations of nutrients by the addition of phosphoric acid along with either calcium ...
Brosnan John T - - 2004
It is now apparent that many of the subtleties of cellular metabolism are intrinsically associated with cell structure and that their physiological study requires techniques that respect the integrity of cells and organs. We have used 15N-substrates to examine urea synthesis in the intact perfused rat liver. This work permits ...
Rutherfurd S M - - 2004
The study aimed to assess the effect of a commercially available microbial phytase added to a corn-soybean meal diet on phytate P and total P in terminal ileal digesta as well as on true ileal amino acid digestibility. Three low-P diets containing 0, 500, or 750 U/kg of microbial phytase ...
Fickers P - - 2004
AIMS: To analyse the influence of nitrogen and carbon sources on extracellular lipase production by Yarrowia lipolytica-overproducing mutant in order to optimize its production in large-scale bioreactors. METHODS AND RESULTS: The level of lipase production and LIP2 induction, measured using an LIP2-LacZ reporter gene, were compared for different carbon and ...
Ba┼čiaçik Karakoç Safak - - 2004
In this study, favorable carbon-nitrogen ratio for high yields of gibberellic acid (GA3) production from Pseudomonas sp. was investigated. First of all, optimum carbon (glucose, maltose, sucrose, fructose, lactose) and nitrogen (KNO3, NH4Cl, NaNO3, urea, glycine) sources among the others were chosen. The highest yield of GA3 productivity was found ...
Katagiri Masayuki - - 2003
In this article, we advocate the radical revision of the 20th-century version of amino acid metabolism as follows. (1) Classic studies on the incorporation of [15N]ammonia into glutamate, once considered to be an epoch-making event, are not distinctive proof of the ability of animals to utilize ammonia for the synthesis ...
Lisiewska Zofia - - 2003
The level of chemical components was determined in seeds of grass pea (Lathyrus sativus L.), cv. Krab, harvested at a dry matter content between 25.9 and 49.6 g/100 g of the raw material, and divided into five degrees of maturity. The results presented suggest that, in general, with an increasing ...
Vanjari Harsha - - 2003
Hydroxamic acids, the naturally occurring and synthetic products, generally have low toxicities and are of interest for many therapeutic applications. The present investigation describes the measurement of hydrogen bond donor (HBD) strength of ten hydroxamic acids by measuring their log P(O/W) values. Hydroxamic acid functional group contains two oxygen and ...
Hanks Jennifer N - - 2003
Wood-decay fungi depend upon recycling of nitrogen-containing molecules to maintain growth in nitrogen-deficient environments. One of the pools that can support growth in these organisms is the pool of free amino acids. The free amino acid (AA) composition of Schizophyllum commune mycelium grown on the surface of nitrogen-rich (M = ...
Koike Toshiyuki - - 2003
Gas mixtures of methane and nitrogen were subjected to proton irradiation (PI), gamma irradiation (GI), UV irradiation (UV) or spark discharges (SD), and the products were analyzed to compare possible energy sources for synthesis of organics in Titan. SD mainly gave unsaturated hydrocarbons, while PI gave saturated hydrocarbons. N-containing organics ...
Scheinkestel C D - - 2003
OBJECTIVES: We wanted to establish optimum protein and glucose intakes during total parenteral nutrition by using a constant caloric but changing protein intake in critically ill, ventilated, anuric patients on continuous renal replacement therapy and measuring amino acid and glucose losses across the hemofilter. METHODS: Eleven consecutive, critically ill patients ...
Hofmann D - - 2003
In order to identify natural nitrogen isotope variations of biologically important amino acids four derivatization reactions (t-butylmethylsilylation, esterification with subsequent trifluoroacetylation, acetylation and pivaloylation) were tested with standard mixtures of 17 proteinogenic amino acids and plant (moss) samples using GC-C-IRMS. The possible fractionation of the nitrogen isotopes, caused for instance ...
Peng Xinhua - - 2003
In the presence of zeolites, moderately deactivated arenes such as 1-nitronaphthalene, naphthonitriles, and methylated benzonitriles can be smoothly nitrated at room temperature by the combined action of nitrogen dioxide and molecular oxygen. The regioselectivity is considerably improved as compared with the conventional nitration methodology based on nitric and sulfuric acids. ...
Li Fu Keung - - 2003
BACKGROUND: Malnutrition is prevalent in patients on continuous ambulatory peritoneal dialysis (CAPD) and confers a poor prognosis. Inadequate nutrient intake is an important contributing factor. Although short-term studies have shown mild to modest nutritional benefit with amino acid dialysate, its long-term effects and tolerability remain obscure. METHODS: The authors have ...
Atkinson M - - 2003
OBJECTIVE: To review the human nutrition in the critically ill patient in a three-part presentation. DATA SOURCES: Articles and published peer-review abstracts and a review of studies reported and identified through a MEDLINE search of the English language literature on parenteral nutrition. SUMMARY OF REVIEW: Intravenous nutrition plays an important ...
Hashimoto Y - - 2003
In 1943, one of the authors (Miura) worked on the nutritional study of Japanese navy sailors. Fortunately the raw data of this study were conserved in secret in the private file of Miura. Recently, another author (Hashimoto) was seeking the data concerning nitrogen balance of Japanese people. Miura, recalling the ...
Judd S J - - 2003
The fate of organic nitrogen and carbon introduced into a swimming pool by pool users has been studied using a 2.2 m(3) model pool. The study made use of a body fluid analogue (BFA), containing the primary endogenous organic amino compounds, and a soiling analogue represented by humic acid (HA). ...
Fruchey Isaac - - 2003
Cyanuric acid hydrolase (AtzD) from Pseudomonas sp. strain ADP was purified to homogeneity. Of 22 cyclic amides and triazine compounds tested, only cyanuric acid and N-methylisocyanuric acid were substrates. Other cyclic amidases were found not to hydrolyze cyanuric acid. Ten bacteria that use cyanuric acid as a sole nitrogen source ...
Veerman Johan J N - - 2003
Several 2-substituted and 2,5-disubstituted piperazine-3,6-diones were synthesized starting from readily available alpha-amino acids. After activation of a lactam carbonyl via introduction of a methoxycarbonyl group onto nitrogen, this carbonyl was selectively reduced. Treatment of the resulting urethane with protic acid generated the corresponding N-acyliminium ion, which was trapped by a ...
Lam Hon-Ming - - 2003
In wild-type Arabidopsis, levels of ASN1 mRNA and asparagine (Asn) are tightly regulated by environmental factors and metabolites. Because Asn serves as an important nitrogen storage and transport compound used to allocate nitrogen resources between source and sink organs, we tested whether overexpression of the major expressed gene for Asn ...
Sawyer Nicole A - - 2003
The abilities of nine genotypes of Amanita muscaria (L.:Fr) Pers. to utilise a range of inorganic and organic nitrogen sources for growth was examined in axenic liquid cultures. Considerable intraspecific variation was observed in biomass yields on all substrates; however biomass yield was highest on glutamine and/or NH4+ for all ...
Sawyer Nicole A - - 2003
The abilities of isolates of Amanita alboverrucosa, A. conicoverrucosa, A. fuscosquamosa, A. nauseosa, A. ochrophylla, A. pyramidifera, A. roseolamellata, A. xanthocephala and six unidentified Amanita species from eastern Australian temperate sclerophyll forests to utilise a range of inorganic and organic nitrogen sources for growth was examined in axenic liquid cultures. ...
Donnermair Martina M - - 2003
The disinfection efficacies of model organic chloramines were investigated. Twenty amino acids and two nucleic acid bases were chlorinated separately with sodium hypochlorite at a Cl:N molar ratio of 0.4:1, and were then used to treat an E. coli suspension for 60 min. DPD/FAS titration was carried out to obtain ...
Singer Michael A - - 2003
Comparative physiological studies are a powerful tool for revealing common animal adaptations. Amino acid catabolism produces ammonia which is detoxified through the synthesis of urea (mammals, some fish), uric acid (birds), or urea and uric acid (reptiles). In mammalian herbivores and omnivores, urea nitrogen is salvaged by a series of ...
Limpens J - - 2003
We tested the relationship between Sphagnum growth and the amount of nitrogen stored in free amino acids in a fertilisation experiment with intact peat monoliths in an open greenhouse in The Netherlands. Three nitrogen deposition scenarios were used: no nitrogen deposition, field conditions and a doubling of the latter, corresponding ...
Wang Xin-Ying - - 2003
AIM: To investigate the formula of amino acid enriched BCAA on nutritional support in traumatic patients after operation. METHODS: 40 adult patients after moderate or large abdominal operations were enrolled in a prospective, randomly and single-blind-controlled study, and received total parenteral nutrition (TPN) with either formula of amino acid (AA ...
Bi J L - - 2003
The impact of urea nitrogen fertilization on silverleaf whitefly, Bemisia argentifolii Bellows & Perring, population dynamics was examined in field-grown cotton (Gossypium hirsutum L.). Five urea nitrogen treatments were tested, consisting of soil applications of 0, 112, 168, and 224 kg nitrogen per hectare, and acombined soil-foliar application of 112:17 ...
Torija María Jesús - - 2003
The effect of tartaric acid and other organic acids on alcoholic fermentation was studied. Organic acids in media with high sugar concentrations and ammonium as the sole nitrogen source had an enormous impact on Saccharomyces cerevisiae metabolism during alcoholic fermentation. The main effect on yeast metabolism was the quick acidification ...
Zubkov Mikhail V - - 2003
Direct evidence that marine cyanobacteria take up organic nitrogen compounds in situ at high rates is reported. About 33% of the total bacterioplankton turnover of amino acids, determined with a representative [(35)S]methionine precursor and flow sorting, can be assigned to Prochlorococcus spp. and 3% can be assigned to Synechococcus spp. ...
Kirchner S - - 2003
Our objective was to understand the influence of dietary gluconeogenic amino acids on hepatic glucose metabolism in rainbow trout (Oncorhynchus mykiss). We analyzed the effects of partial substitution of dietary protein by a single gluconeogenic dispensable amino acid (DAA: alanine, aspartic acid or glutamic acid), on the regulation of hepatic ...
Pageau Karine - - 2003
The role of the host in the nitrogen nutrition of Striga hermonthica (Del.) Benth. (Scrophulariaceae) parasitic on Sorghum bicolor cv. SH4 Arval has been investigated using (15)N-nitrate as the tracer. It is shown that, when nitrate is absorbed only by the roots of the host plant, a rapid transfer of ...
Chew Shit F - - 2003
The freshwater snakehead Channa asiatica is an obligatory air-breather that resides in slow-flowing streams and in crevices near riverbanks in Southern China. In its natural habitat, it may encounter bouts of aerial exposure during the dry seasons. In the laboratory, the ammonia excretion rate of C. asiatica exposed to terrestrial ...
Goldstrohm D A - - 2003
Mosquitoes utilize the amino acids derived from blood meal protein to produce egg proteins. But the amino acids can also be used to produce egg lipid or can be oxidized for energy production. These latter two processes result in the release of nitrogen as toxic ammonia. Therefore, amino acids must ...
Dahlman Lena - - 2003
With the aim of understanding how some lichens can survive intensive fertilization we investigated two green algal ( Trebouxia) lichens, Hypogymnia physodes (L.) Nyl. and Platismatia glauca (L.) W. Culb., and compared control (Ctr), and intensively fertilized (F) thalli. We measured total N, proteins and amino acids to assess lichen ...
Foyer Christine H - - 2003
A key concept underpinning current understanding of the carbon/nitrogen (C/N) interaction in plants is that the capacity for N assimilation is aligned to nutrient availability and requirements by the integrated perception of signals from hormones, nitrate, sugars, organic acids, and amino acids. Studies on the nature and integration of these ...
Wang X D - - 2003
AIMS: To understand the impact of assimilable nitrogen and pantothenic acid on fermentation rate and synthesis of volatile compounds by Saccharomyces under fermentative conditions. METHODS AND RESULTS: A 2 x 3 factorial experimental design was employed with the concentrations of yeast assimilable nitrogen (YAN) (60 and 250 mg l(-1)) and ...
Bely Marina - - 2003
We analyzed the variability of volatile acidity and glycerol production by Saccharomyces cerevisiae on a large sample of high sugar musts. The production of volatile acidity was inversely correlated with the maximum cell population and the assimilable nitrogen concentration. The higher the nitrogen concentration, the less volatile acidity was produced. ...
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