Porphyrin biosynthesis from porphobilinogen by duck blood hemolysate |
| |
Authors: | Rosalia B Frydman Benjamin Frydman Graciela Feinstein |
| |
Institution: | (1) Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junin 956, Buenos Aires, Argentina |
| |
Abstract: | Summary The formation of porphyrins from porphobilinogen by a duck blood hemolysate was examined. The system was found to form mainly protoporphyrin IX and hemin, and accumulated lesser amounts of uroporphyrins, heptacarboxylic porphyrin, and coproporphyrins. By storage at –20° the accumulation of uroporphyrins and heptacarboxylic porphyrin was increased. Both porphyrins were mainly the type III isomers. By addition of dithiothreitol the porphyrin pattern reversed to the original one formed by the fresh hemolysate. Addition of a number of amines also inhibited the decarboxylating system without affecting the original isomer distribution among the porphyrins. Addition of Fe2+ (3mm) did not affect the porphyrin pattern or the isomer distribution. Addition of Pb2+ (2.5mm) partially inhibited the decarboxylating system, whereas at higher concentrations (4mm) it increased the decarboxylation rate of the heptacarboxylic porphyrin. The obtained results are discussed in relation to porphyrin accumulation in porphyria cutanea tarda and in acquired hepatic porphyrias.Dedicated to professorLuis F. Leloir on the occasion of his 70th birthday. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|