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Amino Acids

, Volume 45, Issue 3, pp 413–418 | Cite as

Glutamate: a truly functional amino acid

  • John T. Brosnan
  • Margaret E. Brosnan
Review Article

Abstract

Glutamate is one of the most abundant of the amino acids. In addition to its role in protein structure, it plays critical roles in nutrition, metabolism and signaling. Post-translational carboxylation of glutamyl residues increases their affinity for calcium and plays a major role in hemostasis. Glutamate is of fundamental importance to amino acid metabolism, yet the great bulk of dietary glutamate is catabolyzed within the intestine. It is necessary for the synthesis of key molecules, such as glutathione and the polyglutamated folate cofactors. It plays a major role in signaling. Within the central nervous system, glutamate is the major excitatory neurotransmitter and its product, GABA, the major inhibitory neurotransmitter. Glutamate interaction with specific taste cells in the tongue is a major component of umami taste. The finding of glutamate receptors throughout the gastrointestinal tract has opened up a new vista in glutamate function. Glutamate is truly a functional amino acid.

Keywords

Gamma-carboxyglutamate GI tract Glutathione Insulin secretion Neurotransmitter Umami taste receptors 

Notes

Acknowledgments

The authors’ work was supported by Canadian Institutes of Health Research.

Conflict of interest

None.

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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  1. 1.Department of BiochemistryMemorial University of NewfoundlandSt. John’sCanada

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