Skip to main content
PMC home page
Biochemical Journal logoLink to Biochemical Journal
. 1975 Dec;152(3):705–708. doi: 10.1042/bj1520705

Dimethylnitrosamine demethylation by reconstituted liver microsomal cytochrome P-450 enzyme system.

P D Lotlikar, W J Baldy Jr, E N Dwyer
PMCID: PMC1172528  PMID: 819003

Abstract

Oxidative demethylation of dimethylnitosamine was studied with both reconstituted and unresolved liver microsomal cytochrome P-450 enzyme systems from rats and hamsters. Proteinase treatment of liver microsomal preparations yielded cytochrome P-450 particulate fractions. Both cytochrome P-450 and NADPH- cytochrome c reductase fractions were required for optimum demethylation activity. Particulate cytochrome P-450 fractions were more effecient than either Triton X-100- or cholatesolubilized preparations of these particles in demethylation activity with rat and hamster liver preparations appear to be due to differences in specificity in their cytochrome P-450 fractions.

Full text

PDF
705

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Czygan P., Greim H., Garro A. J., Hutterer F., Schaffner F., Popper H., Rosenthal O., Cooper D. Y. Microsomal metabolism of dimethylnitrosamine and the cytochrome P-450 dependency of its activation to a mutagen. Cancer Res. 1973 Nov;33(11):2983–2986. [PubMed] [Google Scholar]
  2. Druckrey H., Preussmann R., Ivankovic S., Schmähl D. Organotrope carcinogene Wirkungen bei 65 verschiedenen N-Nitroso-Verbindungen an BD-Ratten. Z Krebsforsch. 1967;69(2):103–201. [PubMed] [Google Scholar]
  3. FRISELL W. R., MACKENZIE C. G. The determination of formaldehyde and serine in biological systems. Methods Biochem Anal. 1958;6:63–77. doi: 10.1002/9780470110225.ch3. [DOI] [PubMed] [Google Scholar]
  4. Kawalek J. C., Lu A. Y. Reconstituted liver microsomal enzyme system that hydroxylates drugs, other foreign compounds, and endogenous substrates. VIII. Different catalytic activities of rabbit and rat cytochromes P-448. Mol Pharmacol. 1975 Mar;11(2):201–210. [PubMed] [Google Scholar]
  5. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  6. Lotlikar P. D., Luha L., Zaleski K. Reconstituted hamster liver microsomal enzyme system for N-hydroxylation of the carcinogen 2-acetylaminofluorene. Biochem Biophys Res Commun. 1974 Aug 19;59(4):1349–1355. doi: 10.1016/0006-291x(74)90462-8. [DOI] [PubMed] [Google Scholar]
  7. Lotlikar P. D., Zaleski K. Ring-andN-hydroxylation of 2-acetamidofluorene by rat liver reconstituted cytochrome P-450 enzyme system. Biochem J. 1975 Sep;150(3):561–564. doi: 10.1042/bj1500561. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Lu A. Y., Junk K. W., Coon M. J. Resolution of the cytochrome P-450-containing omega-hydroxylation system of liver microsomes into three components. J Biol Chem. 1969 Jul 10;244(13):3714–3721. [PubMed] [Google Scholar]
  9. Lu A. Y., Levin W., West S., Jacobson M., Ryan D., Kuntzman R., Conney A. H. The role of cytochrome P-450 and P-448 in drug and steroid hydroxylations. Ann N Y Acad Sci. 1973;212:156–174. doi: 10.1111/j.1749-6632.1973.tb47594.x. [DOI] [PubMed] [Google Scholar]
  10. Lu A. Y., West S. B. Reconstituted liver microsomal enzyme system that hydroxylates drugs, other foreign compounds, and endogenous substrates. 3. Properties of the reconstituted 3,4-benzypyrene hydroxylase system. Mol Pharmacol. 1972 Sep;8(5):490–500. [PubMed] [Google Scholar]
  11. Magee P. N., Barnes J. M. Carcinogenic nitroso compounds. Adv Cancer Res. 1967;10:163–246. doi: 10.1016/s0065-230x(08)60079-2. [DOI] [PubMed] [Google Scholar]
  12. Masters B. S., Baron J., Taylor W. E., Isaacson E. L., LoSpalluto J. Immunochemical studies on electron transport chains involving cytochrome P-450. I. Effects of antibodies to pig liver microsomal reduced triphosphopyridine nucleotide-cytochrome c reductase and the non-heme iron protein from bovine adrenocortical mitochondria. J Biol Chem. 1971 Jul 10;246(13):4143–4150. [PubMed] [Google Scholar]
  13. Miller J. A. Carcinogenesis by chemicals: an overview--G. H. A. Clowes memorial lecture. Cancer Res. 1970 Mar;30(3):559–576. [PubMed] [Google Scholar]
  14. Mitani F., Alvares A. P., Sassa S., Kappas A. Preparation and properties of a solubilized form of cytochrome P-450 from chick embryo liver microsomes. Mol Pharmacol. 1971 May;7(3):280–292. [PubMed] [Google Scholar]
  15. Narasimhulu S. Partial resolution of the mixed-function oxidase system of bovine adrenocortical microsomes into two fractions in the absence of detergents. Drug Metab Dispos. 1974 Nov-Dec;2(6):573–576. [PubMed] [Google Scholar]
  16. OMURA T., SATO R. THE CARBON MONOXIDE-BINDING PIGMENT OF LIVER MICROSOMES. I. EVIDENCE FOR ITS HEMOPROTEIN NATURE. J Biol Chem. 1964 Jul;239:2370–2378. [PubMed] [Google Scholar]
  17. Paik W. K., Kim S. Epsilon-alkyllysinase. New assay method, purification, and biological significance. Arch Biochem Biophys. 1974 Nov;165(1):369–378. doi: 10.1016/0003-9861(74)90175-1. [DOI] [PubMed] [Google Scholar]
  18. Venkatesan N., Arcos J. C., Argus M. F. Differential effect of polycyclic hydrocarbons on the demethylation of the carcinogen dimethylnitrosamine by rat tissues. Life Sci. 1968 Oct 1;7(19):1111–1119. doi: 10.1016/0024-3205(68)90217-8. [DOI] [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES