title: Rat liver uroporphyrinogen III synthase has similar properties to the enzyme from Euglena gracilis, including absence of a requirement for a reversibly bound cofactor for activity.
abstract: Uroporphyrinogen III synthase purified from rat liver is a monomer of Mr 36,000 by gel filtration and 28,000 by SDS/polyacrylamide-gel electrophoresis. The enzyme exists in two interconvertible forms separable on h.p.l.c. Both forms of the enzyme could be renatured with full activity after SDS/polyacrylamide-gel electrophoresis, demonstrating the absence of a reversibly bound cofactor. The enzyme activity could be inhibited by pyridoxal 5'-phosphate in the absence and in the presence of NaBH4, consistent with (an) essential lysine residue(s). The enzyme thus shows great similarity to that from Euglena gracilis.
mesh_terms: D000818:Animals; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005056:Euglena gracilis / Q000201:enzymology; D006836:Hydro-Lyases / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D011732:Pyridoxal Phosphate / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D014576:Uroporphyrinogen III Synthetase / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D011732:Pyridoxal Phosphate; D006836:Hydro-Lyases; D014576:Uroporphyrinogen III Synthetase