Abstract
1. A modified porphyrin with inhibitory activity towards protohaem ferro-lyase was purified from the livers of mice treated with 3,5-diethoxycarbonyl-1,4-dihydrocollidine, and partially characterized. 2. The inhibitor can be labelled by 5-amino[4-14C]-laevulinate, suggesting that it originates from pre-labelled liver haem. No radioactivity from 3,5-diethoxycarbonyl-1,4-dihydro[2,6-14C]collidine can be recovered bound to the purified abnormal porphyrin when the radioactive drug is used to induce its formation. 3. Similar modified porphyrins isolated from the livers of animals treated with 2-allyl-2-isopropylacetamide, secobarbitone or 1-ethynylcyclohexanol did not exhibit inhibitory activity toward protohaem ferro-lyase. 4. The inhibition of protohaem ferro-lyase was progressive, could be slowed down by cooling and partially prevented by preincubating the enzyme with the porphyrin substrate. Once established, inhibition could not be reversed by addition of the substrate 5. These results suggest that the modified porphyrin irreversibly inhibits protohaem ferro-lyase and may be used as a sensitive and selective reagent to titrate the number of active centres of the enzyme.
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Selected References
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- Bugany H., Flohe L., Weser U. Kinetics of metal chelatase from rat liver mitochondria. FEBS Lett. 1971 Feb 19;13(2):92–94. doi: 10.1016/0014-5793(71)80206-5. [DOI] [PubMed] [Google Scholar]
- DE MATTEIS F., PRIOR B. E. Experimental hepatic porphyria caused by feeding 3,5-diethoxycarbonyl-1,4-dihydro-2,4,6-trimethylpyridine. Comparison with sedormid porphyria. Biochem J. 1962 Apr;83:1–8. doi: 10.1042/bj0830001. [DOI] [PMC free article] [PubMed] [Google Scholar]
- De Matteis F., Abbritti G., Gibbs A. H. Decreased liver activity of porphyrin-metal chelatase in hepatic porphyria caused by 3,5-diethoxycarbonyl-1,4-dihydrocollidine. Studies in rats and mice. Biochem J. 1973 Jul;134(3):717–727. doi: 10.1042/bj1340717. [DOI] [PMC free article] [PubMed] [Google Scholar]
- De Matteis F., Cantoni L. Alteration of the porphyrin nucleus of cytochrome P-450 caused in the liver by treatment with allyl-containing drugs. Is the modified porphyrin N-substituted? Biochem J. 1979 Oct 1;183(1):99–103. doi: 10.1042/bj1830099. [DOI] [PMC free article] [PubMed] [Google Scholar]
- De Matteis F., Gibbs A. Stimulation of liver 5-aminolaevulinate synthetase by drugs and its relevance to drug-induced accumulation of cytochrome P-450. Studies with phenylbutazone and 3,5-diethoxycarbonyl-1,4-dihydrocollidine. Biochem J. 1972 Mar;126(5):1149–1160. doi: 10.1042/bj1261149. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Honeybourne C. L., Jackson J. T., Jones O. T. The interaction of mitochondrial ferrochelatase with a range of porphyrin substrates. FEBS Lett. 1979 Feb 1;98(1):207–210. doi: 10.1016/0014-5793(79)80185-4. [DOI] [PubMed] [Google Scholar]
- Jones M. S., Jones O. T. The structural organization of haem synthesis in rat liver mitochondria. Biochem J. 1969 Jul;113(3):507–514. doi: 10.1042/bj1130507. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McDonagh A. F., Pospisil R., Meyer U. A. Degradation of hepatic haem to porphyrins and oxophlorins in rats treated with 2-allyl-2-isopropylacetamide. Biochem Soc Trans. 1976;4(2):297–298. doi: 10.1042/bst0040297. [DOI] [PubMed] [Google Scholar]
- ONISAWA J., LABBE R. F. Effects of diethyl-1, 4-dihydro-2, 4,6-trimethylpyridine-3,5-dicarboxylate on the metabolism of porphyrins and iron. J Biol Chem. 1963 Feb;238:724–727. [PubMed] [Google Scholar]
- Ortiz de Montellano P. R., Kunze K. L., Yost G. S., Mico B. A. Self-catalyzed destruction of cytochrome P-450: covalent binding of ethynyl sterols to prosthetic heme. Proc Natl Acad Sci U S A. 1979 Feb;76(2):746–749. doi: 10.1073/pnas.76.2.746. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ortiz de Montellano P. R., Mico B. A., Yost G. S. Suicidal inactivation of cytochrome P-450. Formation of a heme-substrate covalent adduct. Biochem Biophys Res Commun. 1978 Jul 14;83(1):132–137. doi: 10.1016/0006-291x(78)90407-2. [DOI] [PubMed] [Google Scholar]
- Racz W. J., Marks G. S. Drug-induced porphyrin biosynthesis. IV. Investigation of the differences in response of isolated liver cells and the liver of the intact chick embryo to porphyria-inducing drugs. Biochem Pharmacol. 1972 Jan 15;21(2):143–151. doi: 10.1016/0006-2952(72)90264-x. [DOI] [PubMed] [Google Scholar]
- Rifkind A. B. Maintenance of microsomal hemoprotein concentrations following inhibition of ferrochelatase activity by 3,5-diethoxycarbonyl-1,4-dihydrocollidine in chick embryo liver. J Biol Chem. 1979 Jun 10;254(11):4636–4644. [PubMed] [Google Scholar]
- Tephly T. R., Gibbs A. H., De Matteis F. Studies on the mechanism of experimental porphyria produced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine. Role of a porphyrin-like inhibitor of protohaem ferro-lyase. Biochem J. 1979 Apr 15;180(1):241–244. doi: 10.1042/bj1800241. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tephly T. R., Hasegawa E., Baron J. Effect of drugs on heme synthesis in the liver. Metabolism. 1971 Feb;20(2):200–214. doi: 10.1016/0026-0495(71)90092-8. [DOI] [PubMed] [Google Scholar]
