Glutamate monoglutamate

As shown in Figure 10.1, folic acid consists of a pteridine linked at C-9 to p-aminobenzoic acid, forming pteroic acid. The carboxyl group of the p-aminobenzoic acid moiety is linked by a peptide bond to the amino group of glutamate, forming pteroyl monoglutamate. 

Folylpoly-7-glutamate hydrolase catalyzes the hydrolysis of the polyglutamate peptide from intracellular folate-generating folate monoglutamate (135), which can be transported out of the cell." The pteridine ring of the tetrahydrofolate (135) undergoes sequential oxidation to dihydrofolate (137) and... 

As dietary folates pass into the proximal third of the small intestine, folate con-jugases in the brush border of the lumen cleave off glutamate residues to produce the monoglutamate form of folate, which is then absorbed (see Fig. 40.2, upper... 

Synonyms cas 59-30-3 /-n-(p-(((-2-amino-4-hydroxy-6-pteridinyl) methyl>amino)BENZOYL)glutamicacid FOLACIN FOLATE FOLCYSTEINE PTEGLU PTEROYLGLUTAMC ACID PTEROYL-/-GLUTAMIC ACID PTEROYLMONOGLUTAMICACID PTEROYL-/-MONOGLUTAMIC ACID VITAMIN BC VITAMIN M... 

Several active derivatives of the vitamin are known to occur, these containing up to 11 glutamate residues in the molecule. The monoglutamate form is readily absorbed from the digestive tract but the polyglutamates must be degraded by enzymes to the monoglutamate form before they can be absorbed. 

Folate polyglutamates are the preferred substrates for folate-dependent enzymes they are more active metabolically in cells and also better retained in cells than folate monoglutamates. Natural folates found in foods are all conjugated to a polyglutamyl chain containing different numbers of glutamic adds depending on the type of food. 

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