Biosynthesis of porphyrins in Rhodopseudomonas palustris-VI. The effect of metals, thiols and other reagents on the activity of uroporphyrinogen decarboxylase

• Autores: Koopmann, G.E.; Del C. Batlle, A.M.
• Año de publicación: 1987
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Int. J. Biochem. 1987;19(4):373-377
• Materia: 4 chloromercuribenzoic acid; 5,5' dithiobis(2 nitrobenzoic acid); Carboxy Lyases; carboxylyase; copper; ferrous ion; mercury; metal; p Chloromercuribenzoic Acid; porphyrin; thiol derivative; uroporphyrinogen decarboxylase; zinc; article; biosynthesis; metabolism; Rhodopseudomonas; Carboxy-Lyases; Chloromercuribenzoates; Copper; Dithionitrobenzoic Acid; Ferrous Compounds; Mercury; Metals; p-Chloromercuribenzoic Acid; Porphyrins; Rhodopseudomonas; Sulfhydryl Compounds; Support, Non-U.S. Gov't; Uroporphyrinogen Decarboxylase; Zinc
• Institución: Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales

1. 1. The effect of several metals and reagents on the decarboxylation rate of uroporphyrinogen I by using a 16-fold purified preparation of Uroporphyrinogen Decarboxylase from Rhodopseudomonas palustris, was studied. 2. 2. 1 mM Hg2+ and Cu2+ were strong inhibitors, 1 mM Zn2+ and Fe2+ under certain conditions and 1 mM Fe3+ and Cr3+ also inactivated the enzyme, but Pb2+, Cd2+, and Al3+ did not. Metals inhibition was reversed by 1 mM GSH or CvSH. 3. 3. 0.1 mM DTNB and PCMB, 1 mM pyridoxal phosphate and 100 mM chloral hydrate, as well as 1 mM 2-methoxy-5-nitrotropone and 0.2 mM diethylpyrocarbonate inhibited Uroporphyrinogen Decarboxylase; while GSH, CySH, N-ethylmaleimide, sodium thioglycolate, 1,4-dithioerythritol, EDTA and O-phenantroline did not modify activity. 4. 4. Data obtained would indicate that one cysteine, one or two histidine residues and probably a lysine group are required for enzyme activity. © 1987.
Fil:Del C. Batlle, A.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.