A Method for the Determination of Formiminoglutamic Acid in Urine1

Abstract
A sensitive spectrophotometric method is presented for the assay of formiminoglutamic acid in urine. This is based on the enzymatic reactions: (1) formiminoglutamic acid + tetrahydrofolic acid 5-formiminotetrahydrofolic acid + glutamic acid; (2) 5-formiminotetrahydrofolic acid [forward arrow]5,10-methenyl-tetrahydrofolic acid + NH3. Quantitative determination of 5,10-methenyl-tetrahydrofolic acid is carried out spectrophotometrically.