Formation of N tau-ribosylhistidine, a novel histidine derivative found in the urine in histidinemia, from histidine and NAD(P)+ catalyzed by an NAD(P)+ glycohydrolase system.
The formation of N tau-ribosylhistidine (His-R), a novel histidine derivative found in the urine of histidinemic patients, was studied. A most possible synthetic pathway catalyzed by imidazole acetic acid (ImAA) phosphoribosyltransferase was not substantiated, because p.o. administration to humans and rats of aspirin, an inhibitor of the enzyme, did not change the urinary excretion of His-R, whereas aspirin decreased the excretion of ImAA-R with concomitant increase in that of ImAA. His-R was produced on incubation of a rat liver homogenate or its membrane fraction with histidine, NAD(P)+ and MgCl2, but not with only histidine or NAD(P)+. Nicotinamide inhibited the formation of His-R. Thus the enzymes responsible for the formation of His-R were suggested to be NAD(P)+ nucleosidase, nucleotide pyrophosphatase and 5'-nucleotidase.
Imamura
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I
Watanabe
T
T
Wada
H
H
D015720:5'-Nucleotidase; D000818:Animals; D001241:Aspirin / Q000494:pharmacology; D006632:Histamine / Q000652:urine; D006639:Histidine / Q000031:analogs & derivatives* / Q000097:blood* / Q000652:urine; D006801:Humans; D008099:Liver / Q000378:metabolism; D008274:Magnesium / Q000494:pharmacology; D015636:Magnesium Chloride; D009244:NAD+ Nucleosidase / Q000378:metabolism*; D009249:NADP / Q000378:metabolism*; D009536:Niacinamide / Q000494:pharmacology; D009708:Nucleotidases / Q000378:metabolism*; D011755:Pyrophosphatases / Q000378:metabolism*; D051381:Rats
D015636:Magnesium Chloride; D009536:Niacinamide; D006639:Histidine; D009249:NADP; D006632:Histamine; C046248:N(tau)-ribosylhistidine; D009708:Nucleotidases; D015720:5'-Nucleotidase; D009244:NAD+ Nucleosidase; D011755:Pyrophosphatases; C021899:nucleotide pyrophosphatase; D008274:Magnesium; D001241:Aspirin