Abstract
Cytochrome P450 was first shown to be a hemoprotem in 1964 (1). It has as its prosthetic group a noncovalently bound iron protoporphyrin IX, a form of heme found in b-type cytochromes, like cytochrome b, hemoglobin, and myoglobm. This type of heme prosthetic group can be removed from the protein by acidic acetone or by alkali and pyridine. There are a number of methods that can be used for spectrophotometrrc analysis of hemoproteins, each useful for a different purpose. In this chapter, we will provide methods for quantifying cytochrome P450, as well as methods for studying substrate interaction with the purified protein, the hemoprotem in membranes, and in tissue homogenates. The ability of those hemoproteins with an available 6th coordination position to bind small molecules such as cyanide, carbon monoxide, ethyl isocyanide, etc., has provided means for their analysis and quantification. In the case of cytochrome P450, the binding of carbon monoxide permitted demonstration of its mvolvement in the monooxygenase reaction.
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References
Omura, T. and Sato, R. (1964) The carbon monoxtde-bmdmg pigment of liver microsomes I Evidence for its hemoprotein nature. J Biol Chem 239, 2370–2378.
Paul, K., Theorell, H, and Akeson, A. (1953) The molar ltght absorptton of pyrtdine ferroprotoporphyrm (pyridine haemochromogen) Acta Chem Stand 7, 1284–1287
Cmtr, D and Schenkman, J (1972) Hepattc organelle mteractton. 1. Spectral mvestigation during drug biotransformatton. Mol. Pharmacol 8, 327–338
Raw, I. and Mahler, H (1959) Studies of electron transport enzymes III. Cytochrome b5 of pig liver mitochondrta J Biol Chem 234, 1867–1873
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© 1998 Humana Press Inc.
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B. Schenkman, J., Jansson, I. (1998). Spectral Analyses of Cytochromes P450. In: Phillips, I.R., Shephard, E.A. (eds) Cytochrome P450 Protocols. Methods in Molecular Biology™, vol 107. Humana Press. https://doi.org/10.1385/0-89603-519-0:25
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DOI: https://doi.org/10.1385/0-89603-519-0:25
Publisher Name: Humana Press
Print ISBN: 978-0-89603-519-5
Online ISBN: 978-1-59259-580-8
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