amino acid dehydrogenases (l-amino acid: oxidoreductase deaminating ec 1.4.1.x) are members of the wider superfamily of oxidoreductases that catalyze the reversible oxidative deamination of an amino acid to its keto acid and ammonia with the concomitant reduction of either nad+, nadp+ or fad. these enzymes have been received much attention as biocatalysts for use in biosensors or diagnostic kit...

INTRODUCTION Glutamine rate of appearance (Ra) may be used as an estimate of endogenous glutamine production. Recently a technique employing a bolus injection of isotopically labeled glutamine was introduced, with the potential to allow for multiple assessments of the glutamine Ra over time in critically ill patients, who may not be as metabolically stable as healthy individuals. Here the techn...

To assess the effect of glutamine availability on rates of protein synthesis in human enterocytes, Caco-2 cells were grown until differentiation and then submitted to glutamine deprivation produced by exposure to glutamine-free medium or methionine sulfoximine [L-S-[3-amino-3-carboxypropyl]-S-methylsulfoximine (MSO)], a glutamine synthetase inhibitor. Cells were then incubated with (2)H(3)-labe...

Many mammalian cancer cell lines depend on glutamine as a major tri-carboxylic acid (TCA) cycle anaplerotic substrate to support proliferation. However, some cell lines that depend on glutamine anaplerosis in culture rely less on glutamine catabolism to proliferate in vivo. We sought to understand the environmental differences that cause differential dependence on glutamine for anaplerosis. We ...

Viruses rewire host cell glucose and glutamine metabolism to meet the bioenergetic and biosynthetic demands of viral propagation. However, the mechanism by which viruses reprogram glutamine metabolism and the metabolic fate of glutamine during adenovirus infection have remained elusive. Here, we show MYC activation is necessary for adenovirus-induced upregulation of host cell glutamine utilizat...

We measured glutamine kinetics using L-[5-15N]glutamine and L-[ring-2H5]phenylalanine infusions in healthy subjects in the postabsorptive state and during ingestion of an amino acid mixture that included glutamine, alone or with additional glucose. Ingestion of the amino acid mixture increased arterial glutamine concentrations by approximately 20% (not by 30%; P < 0.05), irrespective of the pre...

Glutamine synthetase purified to apparent homogeneity from Bacillus subtilis is subject to feedback inhibition by multiple end products of glutamine metabolism, as well as by the reaction product L-glutamine. AMP, glutamine, and histidine are potent inhibitors when any of the substrates glutamate, MnATP, or ammonia are present in limiting concentration during assay, but the strong inhibition by...

oral glutamine supplementation is highly effective in preventing and delaying radiation-induced esophagitis, one of the most common discomforting side effects of radiation to the thoracic area among lung cancer patients. according to the literature, lung cancer is the leading cause of death among all cancers with the highest incidence worldwide. this paper aims to emphasize the importance of or...

Recent research has shown that the amino acid glutamine can positively affect gut health by supporting microbiome, mucosal wall integrity, and modulating inflammatory responses. As modulated vagus nerve, via enteric nervous system, gut-brain connection impact brain's neurochemical environment. Poor disrupt balance of neurotransmitters, which result in neuropsychiatric based conditions such as d...

Recently, we demonstrated that supplementing (with 3 mg Se per day) the diets of growing beef steers grazing on Se-deficient toxic endophyte-infected tall fescue-based forage with either organic (OSe, SEL-PLEX) or a 1:1 blend (MIX) OSe and inorganic (ISe, sodium selenite) in vitamin–mineral mixes, rather than forms Se, ameliorated several classic serum symptoms fescue toxicosis. Importantly, hi...