Glutamine, a conditionally essential amino acid, is consumed predominantly in the gastrointestinal tract as a source of energy, particularly under the conditions of trauma, sepsis and surgery. In this article, we discuss the unique role of glutamine in the preservation of epithelial barrier function in the gastrointestinal tract. Glutamine supplementation protects the gastrointestinal mucosal h...

stimulates glutamine release at the expense of tissue glutamate while decreasing or having little effect on alanine release (Ruderman & Lund, 1972; Chang & Goldberg, 1978). In the perfused rat hindlimb total glutamine production by resting muscle is over 4-fold greater than ammonia production, but the addition of methionine sulphoximine (a glutamine synthetase inhibitor) reverses this pattern (...

We have examined three mutants of Klebsiella aerogenes whose genetic lesions (glnB, glnD, and glnE) are in loci unlinked to the structural gene for glutamine sythetase (glnA) and in which the control of both the level and state of adenylylation of glutamine synthetase is altered. Each mutation alters a different component of the adenylylation system of glutamine synthetase [L-glutamate:ammonia ...

The capacity of rat neutrophils to utilize glutamine was investigated by 1) determination of oxygen consumption in the presence of glucose or glutamine, 2) measurement of maximal activity of phosphate-dependent glutaminase, 3) Northern blot, Western blot, and immunocytochemical detection of glutaminase, and 4) measurement of glutamine utilization and also production of ammonia, glutamate, aspar...

Recent studies highlight the importance of glutamine metabolism in metabolic reprogramming, which underlies cancer cell addiction to glutamine. Examples for the dependence on glutamine metabolism are seen across different tumor types as during different phases of cancer development, progression and response to therapy. In this perspective, we assess the possibility of targeting glutamine metabo...

The structural gene for glutamine synthetase, glnA, from Amycolatopsis mediterranei U32 was cloned via screening a genomic library using the analog gene from Streptomyces coelicolor. The clone was functionally verified by complementing for glutamine requirement of an Escherichia coli glnA null mutant under the control of a lac promoter. Sequence analysis showed an open reading frame encoding a ...

We investigated the effects of glutamine and histidine analogues on glutamine transport processes in membrane vesicles prepared from rat liver (sinusoidal membrane) and skeletal muscle (sarcolemma). L-[14C]Glutamine is transported in these membranes predominantly by Systems N/Nm (liver and muscle respectively), and to a lesser extent by Systems A and L (e.g. about 60, 20 and 20% of total flux r...

1. The activities of the two key enzymes involved in glutamine metabolism, glutaminase and glutamine synthetase, were measured in mucosal biopsies taken from different sites throughout the human gastrointestinal tract, from oesophagus to rectum. 2. The specific activity of glutamine synthetase was highest in the stomach (4.5 nmol glutamine formed per minute per mg of protein), but both small an...

HYPOTHESIS the endovenous administration of glutamine, independently of the type of nurtrition received, can reduce the ICU length of stay, the incidence of infections and the mortality in the traumatic patients admitted to the ICU. OBJECTIVES The main objective is to assess the efficacy of glutamine suplementation, given intravenously, to reduce the incidence of infectious complications, mor...

Glutamine is the primary metabolite of nitrogen assimilation from inorganic nitrogen sources in microorganisms and plants. The ability to monitor cellular nitrogen status is pivotal for maintaining metabolic homeostasis and sustaining growth. The present study identifies a glutamine-sensing mechanism common in the entire plant kingdom except Brassicaceae. The plastid-localized PII signaling pro...