Glutamine utilization

GMP synthetase [EC 6.3.4.1], also known as xanthosine-5 -phosphate ammonia ligase, catalyzes the reaction of ATP with xanthosine 5 -phosphate and ammonia to produce GMP, AMP, and pyrophosphate (or, diphosphate). GMP synthetase (glutamine-utilizing) [EC 6.3.5.2] catalyzes the reaction of ATP with xanthosine 5 -phosphate, L-glutamine, and water to produce GMP, AMP, L-glutamate, and pyrophosphate. 

Butler M, Spier RE (1984), The effects of glutamine utilization and ammonia production on the growth of BHK cells in microcarrier cultures, J. Biotechnol. 1 187-196. 

Petch D, Butler M (1994), Profile of energy metabolism in a murine hybridoma glucose and glutamine utilization,). Cell. Physiol. 161 71-76. 

Zeng AP, Deckwer WD (1995b), Mathematical modeling and analysis of glucose and glutamine utilization and regulation in cultures of continuous mammalian cells, Biotechnol. Bioeng. 47 334-346. 

Glutamine utilization by the gut is diminished by a metabolic acidosis compared with the postabsorptive or postprandial states. During metabolic acidosis, the uptake of glutamine by the kidney is increased, and blood glutamine levels decrease. As a consequence, the gut takes up less glutamine. 

Ito, K. and Uchino, H. Control of pyrimidine biosynthesis in human lymphocytes. Induction of glutamine-utilizing car-bamyl phosphate synthetase and operation of orotic acid pathway during blastogenesis. J. Biol. Chem., 246, 4060-4065 (1971)... 

The glutamine synthetase of E. coli is partially inhibited by adenylate, being maximally inhibited only in the presence of products of eight different glutamine-utilizing pathways. The interpretation of these results is complicated b> the more recent discovery of two forms of glutamine synthetase in this organism and of the two enzymes required for their interconversion (54)- The sheep brain enzyme is not subject to these kinds of control mechanism (66). 

Several other analogs might be considered as potential competitive inhibitors of glutamine utilization. These include 0-carbamyl-L-serine,... 

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