Porphobilinogen deaminase and the synthesis of porphyrin isomers in the Dubin-Johnson syndrome.
Porphyrin synthesis was studied in a family of 9.3 of whom had the Dubin-Johnson syndrome (DJS). Subjects with DJS had modest increases in urinary porphyrin concentration with a marked increase in the series I isomer of coproporphyrin (tetracarboxylic) as well as in the octa-, hepta-, hexa- and penta-carboxyl porphyrins. Activity of erythrocyte porphobilinogen deaminase (PBG-D) was also increased. Non-expressing carriers in the family had normal levels of urinary porphyrins but modest increases in both series I isomer accumulation and PBG-D activity. These results may provide a rationale for the altered synthesis of porphyrin in DJS.
D000293:Adolescent; D000328:Adult; D000642:Ammonia-Lyases / Q000097:blood*; D002648:Child; D004912:Erythrocytes / Q000201:enzymology*; D005260:Female; D006801:Humans; D011163:Hydroxymethylbilane Synthase / Q000097:blood*; D007566:Jaundice, Chronic Idiopathic / Q000201:enzymology* / Q000235:genetics; D008297:Male; D010375:Pedigree; D011166:Porphyrins / Q000652:urine
D011166:Porphyrins; D011163:Hydroxymethylbilane Synthase; D000642:Ammonia-Lyases