Glutamic acid is a nonessential amino acid is derived from the diet and from the breakdown of gut proteins. Glutamate is a major excitatory neurotransmitter in the brain. It plays a role in neuronal differentiation, migration, and survival in the developing brain. It is also involved in synaptic maintenance, neuroplasticity, learning, and memory. Glutamate is present in many foods including cheese, seafood, meat, and spinach. In spite of intake, the total pool of glutamic acid in the blood is small, due to its rapid uptake and utilization by tissues including muscle and the liver (which uses it to form glucose and lactate). Glutamic acid is also the precursor for arginine, glutamine, proline, GABA, and the polyamines (putrescine, spermine, spermidine). The Cahill Cycle is used to generate pyruvate and glucose in the liver using branch chain amino acids. Glutamate is an end product of this reaction via the enzyme alanine aminotransferase (ALT). Glutamate is also an end product of the enzyme ornithine aminotransferase (OAT) in the urea cycle. This urea cycle reaction is a vitamin B6-dependent enzyme which catalyzes the reversible conversion of ornithine to alpha-ketoglutarate, yielding glutamate.
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Glutamic Acid
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