M. Kinuta, T. Ubuka, K. Yao
Apr 1, 1992
Citations
0
Influential Citations
8
Citations
Quality indicators
Journal
The Biochemical journal
Abstract
S-[2-Carboxy-1-(1H-imidazol-4-yl)ethyl]cysteine (I), a proposed precursor of 3-[(carboxymethyl)thio]-3-(1H-imidazol-4-yl)propanoic acid [Kinuta, Yao, Masuoka, Ohta, Teraoka & Ubuka (1991) Biochem. J. 275, 617-721], was isolated from healthy human urine by using ion-exchange column chromatography. Identification of the isolated compound with compound (I) was performed by physicochemical analyses involving i.r., m.s. and n.m.r. spectrometries as well as high-voltage paper electrophoresis, t.l.c. and paper chromatography. Compound (I) was synthesized in 80% yield by incubation of a reaction mixture containing trans-urocanic acid and 3-fold excess of cysteine at 70-75 degrees C. From these results we suggest that natural thiol compounds such as cysteine and GSH participate in the metabolism of urocanic acid, a key metabolite of L-histidine.