Uroporphyrinogen I synthase

Figure 32-8. Steps in the biosynthesis of the porphyrin derivatives from porphobiiinogen. Uroporphyrinogen i synthase is aiso caiied porphobiiinogen deaminase or hydroxymethyibiiane synthase.

Acute Intermittent Porphyria Uroporphyrinogen-I Synthase Deficiency... 

The pyrrole monomer porphobilinogen arises from the condensation of two molecules of S-aminolevulinate with the ions of two water molecules. This reaction is catalyzed by S-aminolevulinate dehydrase. Condensation of four porphobilinogen molecules yields the branchpoint compound in tetrapyrrole synthesis, uroporphyrinogen III. This is a complex reaction requiring two enzymes Uroporphyrinogen I synthase, which catalyzes a head-to-tail condensation... 

D-12) Uroporphyrinogen I synthase deficiency (acute intermittent porphyria). 

Acute intermittent porphyria AtP Uroporphyrinogen I synthase autosomal dominant... 

Porphobilinogen deaminase (PBGD) Cytosolic enzyme that processes six PEG molecules through a hexapyrrole adduct to catalyze the formation of a free linear tetrapyrrole, hydroxymethylbilane (aka uroporphyrinogen I synthase). 

Alexopoulos CG, Chalevelakis G, Katsoulis C, Pallikaris G (1986) Adverse effects of cis-diamminedichloroplatinum II (CDDP) on porphyrin metabolism in man. Cancer Chemother Pharmacol 17 165-170 Anderson PM, Desnick RJ (1980) Purification and properties of uroporphyrinogen I synthase from human erythrocytes. J Biol Chem 255 1993-1999 Angle CR (1993) Childhood lead poisoning and its treatment. Annu Rev Pharmacol Toxicol 32 409-434... 

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