Disease relevance of ammonia

• The crystal structure of the Escherichia coli AmtB-GlnK complex reveals how GlnK regulates the ammonia channel [1].
• The resultant ammonia toxicity might exacerbate the neurological deficits of HD [2].
• Nitrogen 15 tracer studies on the pathway of denitrification in Pseudomonas aeruginosa [3].
• The dynamic properties of ribosomal protein L9 from Bacillus stearothermophilus were investigated in solution using an analysis of nitrogen-15 longitudinal and transverse relaxation rates and amide nitrogen-proton nuclear Overhauser effects [4].
• d-Amino acid amidase (DAA) from Ochrobactrum anthropi SV3, which catalyzes the stereospecific hydrolysis of d-amino acid amides to yield the d-amino acid and ammonia, has attracted increasing attention as a catalyst for the stereospecific production of d-amino acids [5].

Psychiatry related information on ammonia

• In anorexia nervosa patients, biochemical abnormalities in the serum were more frequent in total serum protein (93%), blood sugar (85%), and globulins (78%) than in other serum factors, such as blood urea nitrogen (15%), uric acid (15%), and alkaline phosphatase (7%) [6].

High impact information on ammonia

• In Escherichia coli, previous studies have indicated that binding of the P(II) signal transduction protein GlnK to the ammonia channel AmtB regulates the channel thereby controlling ammonium influx in response to the intracellular nitrogen status [1].
• The dependence of T1 and nuclear Overhauser effects upon correlation time is discussed, and preliminary nitrogen-15 nuclear magnetic resonance results for several biopolymers, including lysozyme, protamines, pepsin, hemoglobin, vitamin B 12, and tRNA, are presented [7].
• Microglia also degrade fAbeta if lysosomes are acidified by an ammonia pulse-wash or by treatment with forskolin, which activates protein kinase A. Our results indicate that regulated lysosomal acidification can potentiate fAbeta degradation by microglia [8].
• Detailed nitrogen-15 relaxation measurements indicate that Ca2+ may facilitate the adaptive recognition of the substrate by inducing slow micro- to millisecond time-scale dynamics in the active site [9].
• 0. Only an averaged azide signal was observed in the nitrogen-15 NMR spectra for solutions that contained the azide complex of chloroperoxidase, horseradish peroxidase, and myoglobin [10].

Chemical compound and disease context of ammonia

• Assignment of the three methionyl carbonyl carbon resonances in Streptomyces subtilisin inhibitor by a carbon-13 and nitrogen-15 double-labeling technique. A new strategy for structural studies of proteins in solution [11].
• NMR study of nitrogen-15-labeled Escherichia coli valine transfer RNA [12].
• Air hygiene parameters were measured 24 h/day for 7 days with each bedding type: ammonia (NH3), inhalable and respirable dust, endotoxins, colony forming units (CFU) of total mesophilic bacteria, fungi, actinomycetes and thermophilic actinomycetes [13].
• Linkage region between core and the O-chain of the lipopolysaccharide from Bordetella hinzii has been analyzed by NMR and MS analysis of the products, obtained by anhydrous HF treatment or consecutive ammonia and AcOH treatment of the LPS [14].
• BACKGROUND: The glutamate synthase operon (gltBDF) contributes to one of the two main pathways of ammonia assimilation in Escherichia coli [15].

Biological context of ammonia

• The exchange kinetics of over 70% of the 143 backbone amide hydrogens in staphylococcal nuclease H124L (nuclease H124L), both in its unligated state and in its ternary complex with Ca2+ and thymidine 3',5'-bisphosphate, have been quantified by nitrogen-15 resolved proton nuclear magnetic resonance spectroscopy [16].
• Indeed, some 40% of the backbone amide groups of hTGF alpha, including many at the interface between the two subdomains, exhibit significant nitrogen-15 chemical-exchange line broadening indicative of interconversions between multiple protein conformations on the microsecond time scale [17].
• Hypoosmotic swelling and ammonia increase oxidative stress by NADPH oxidase in cultured astrocytes and vital brain slices [18].
• Deamination of these two compounds results in the release of ammonia, which is used as a source of nitrogen for bacterial growth [19].
• In this study, we tested an array of metabolites including, glucose 6-phosphate, fructose 6-phosphate, fructose 1,6-bisphosphate, 3-phosphoglycerate (3-PG), glucose 1-phosphate, glucose 1,6-bisphosphate, ADP, carnitine, acetylcarnitine, IMP, inosine, and ammonia for allosteric regulation [20].

Anatomical context of ammonia

• Starting with the gene, the cell-free system, and milligram amounts of nitrogen-15 isotopically enriched amino acids, sufficient protein is produced in 4 h to obtain a high-resolution 2D HSQC spectrum of the protein in 40 min [21].
• Also ammonia induced a rapid ROS production in cultured astrocytes and brain slices, which was sensitive to apocynin [18].
• Nitrogen-15 NMR relaxation parameters have been recorded for the N-terminal domain of the rat T-cell antigen CD2 (CD2d1) in a dilution series from 1.20 mM to 40 microM (pH 6.0, 25 degrees C) [22].
• Comparative in vivo nitrogen-15 nuclear magnetic resonance study of the cell wall components of five Gram-positive bacteria [23].
• A possible cell source for a bio-artificial liver is the human hepatblastoma-derived cell line HepG2 as it confers many hepatocyte functions, however, the urea cycle is not maintained resulting in the lack of ammonia detoxification via this cycle [24].

Associations of ammonia with other chemical compounds

• A new method for selective excitation in biomolecular NMR uses two-fold single-transition cross-polarization between protons and nitrogen-15 or carbon-13 nuclei [25].
• The nitrogen-15 magnetic resonance of glycine [26].
• Investigation of proton transport tautomerism in clusters of protonated nucleic acid bases (cytosine, uracil, thymine, and adenine) and ammonia by high-pressure mass spectrometry and ab initio calculations [27].
• The energetics of the ion-molecule interactions and structures of the clusters formed between protonated nucleic acid bases (cytosine, uracil, thymine, and adenine) and ammonia have been studied by pulsed ionization high-pressure mass spectrometry (HPMS) and ab initio calculations [27].
• The crystal structure of the ammonia transport (Amt) protein AmtB at 1.4 A resolution revealed four ammonia/ammonium (NH3/NH4+) binding sites along the approximately 20 A narrow pore [28].

Gene context of ammonia

• In this study, we investigated the pH titration behavior of the carboxyl groups of the N-terminal domain of rat CD2 (CD2d1) using the chemical shifts of backbone amide nitrogen-15 ((15)N) and proton NMR resonances, and carboxyl carbon-13 ((13)C) signals [29].
• Significant within-group differences were found for the PLC group: CORT before compared with immediately after exercise; INS before compared with immediately after exercise and before compared with 1.5 hours after exercise; and AMM before compared with immediately after exercise and before compared with 1.5 hours after exercise [30].
• Analysis of the hyperfine-shifted nitrogen-15 resonances of the oxidized form of Anabaena 7120 heterocyst ferredoxin [31].
• Multinuclear magnetic resonance studies of the 2Fe.2S* ferredoxin from Anabaena species strain PCC 7120. 3. Detection and characterization of hyperfine-shifted nitrogen-15 and hydrogen-1 resonances of the oxidized form [32].
• Evidence from nitrogen-15 and solvent deuterium isotope effects on the chemical mechanism of adenosine deaminase [33].

Analytical, diagnostic and therapeutic context of ammonia

• The dynamic aspects of protein metabolism in uremic children were studied by using newly developed gas chromatography and mass spectrometry micromethods for determining nitrogen-15 enrichment in plasma lysine during a continuous i.v. infusion of 15N-lysine [34].
• This organ is responsible for most of the excretory processes (ultrafiltration, reabsorption and secretion) and secretes an acidic ammonia-rich excretory fluid [35].
• The quantitative determinations have been carried out by selective titrations in aqueous solutions, thermal programmed desorption connected to mass spectrometry (TPD-MS), and ammonia adsorption-desorption, measured by thermogravimetry (TG) [36].
• A sequential upflow anaerobic sludge blanket (UASB) and air-lift loop sludge blanket (ALSB) treatment was introduced into leachate recirculation to remove organic matter and ammonia from leachate in a lab-scale bioreactor landfill [37].
• Treatment of chromomycosis by cryosurgery with liquid nitrogen: 15 years' experience [38].

References