Glutamic acid is one of the 20-22 proteinogenic amino acids and its codons are GAA and GAG. It is one of so called nonessential amino acids, animals can synthesize it from α-ketoglutarate, formed in the metabolism of carbohydrates. The two carboxyl groups of glutamate dissociate at physiological conditions, carboxylate anions form salts with Na+, K+ cations. The salts of glutamic acid are known as glutamates. The substance was discovered and identified in the year 1866, by the German chemist L. Ritthausen from wheat gluten, for which it was named glutamic acid.
Glutamate is a key compound in cellular proteins - amino acids metabolism. A key reactions in amino acids degradation are transamination, oxidative deamination and decarboxylation. In all these reactions the central player is amino acid - glutamate.
Glutamate is important neurotransmitter for the central nervous system. Neurotransmitters (glutamate) transmit across a synapse nerve impuls signals from a neuron to a target cell glutamate receptor. When the neurotransmitter binds to a receptor molecule, changes the nerve cell membrane electrical potential, which is slowing the spread below.
L-glutamic acid or glutamate is proteinogenic amino acid, like the other natural L-amino acids is present in all protein in the diet. Glutamate can be only tested when it is present in proteins in an unbound form it is free glutamate. Significant amounts of free glutamic acid are present in a wide variety of foods, including dairy products (parmesan cheese, human milk), poultry products (duck, chicken), fish (pilchard, mackerel, salmon) vegetables (peas, corn, tomatoes, potato).
At the beginning of 20th century Japanese researcher K. Ikeda identified glutamate from seaweed, when tasted undeniable flavor, called umami (savoury deliciousness). Glutamic acid, monosodium glutamate and relating compounds often used as a food additive and flavor enhancer in the form of its salt, known as monosodium glutamate (MSG).
Keywords: glutamic acid, monosodium glutamate (MSG), metabolism, neu ro trans mitter, food additives (E620-625).
