title: N tau-Ribosylhistidine, a novel histidine derivative in urine of histidinemic patients. Isolation, structure, and tissue level.
abstract: On amino acid analysis of urine of histidinemic patients, an unidentified compound was eluted in a position between beta-aminoisobutyric acid and gamma-aminobutyric acid. This compound was purified to homogeneity from the urine by a combination of extraction with 80% ethanol, repeated column chromatography on Bio-Rad AG-50, and high performance liquid chromatography on a strongly cationic ion exchanger. The compound yielded free histidine on hydrolysis in an evacuated sealed tube with 0.1-6.0 M HCl at 145 degrees C for 5 h, but not at 100 degrees C for 24 h. This compound was determined to be N tau-ribosylhistidine by 1H and 13C NMR spectroscopies. The urinary content of this material in normal and histidinemic children was 17.8 +/- 13.4 (n = 10) and 126 +/- 51 (n = 14) mumol/g creatinine (mean +/- S.D.), respectively, and were closely correlated with those of urinary histidine. The renal clearance value of N tau-ribosylhistidine in humans was 96% of that of creatinine. When rats were fed on diets rich in histidine, the urinary excretion of N tau-ribosylhistidine increased greatly and was well correlated with the intake of histidine.
mesh_terms: D000592:Amino Acid Metabolism, Inborn Errors / Q000652:urine*; D000596:Amino Acids / Q000097:blood / Q000652:urine; D000818:Animals; D006639:Histidine / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism* / Q000652:urine; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D014018:Tissue Distribution
chemical_list: D000596:Amino Acids; D006639:Histidine; C046248:N(tau)-ribosylhistidine