title: Photodynamic inactivation of red cell uroporphyrinogen decarboxylase by porphyrins.
abstract: The effects of light and porphyrins on the activity of red cell uroporphyrinogen decarboxylase were studied. Photoinactivation of uroporphyrinogen decarboxylase was dependent on uroporphyrin concentration, irradiation time and temperature. Using 40 W/m2 of UV light intensity, 40-45% decreased activity was produced with 200 microM uroporphyrin I, at 37 degrees C and after 2 hr of illumination. It has been demonstrated that porphyrins photoinactivate uroporphyrinogen decarboxylase and a mechanism for this action in relation to skin lesions is proposed.
mesh_terms: D002262:Carboxy-Lyases / Q000097:blood*; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D007700:Kinetics; D010782:Photolysis; D011166:Porphyrins / Q000494:pharmacology*; D013816:Thermodynamics; D014466:Ultraviolet Rays; D014575:Uroporphyrinogen Decarboxylase / Q000037:antagonists & inhibitors / Q000097:blood* / Q000528:radiation effects
chemical_list: D011166:Porphyrins; D002262:Carboxy-Lyases; D014575:Uroporphyrinogen Decarboxylase