[Identification of various hydrophobic zones in microsomal membranes containing cytochrome P-450 binding sites for type I and II substrates].
Two different phospholipid hydrophobic zones in the membrane associated with cytochrome P-450 were identified. One of them exhibits selective sensitivity towards the protonated influence of carbonylcyanide-m-chlorophenyl hydrazone and possesses binding sites for type I substrates. The second one includes the heme group of cytochrome P-450 and herein the binding sites for type II substrates. Sodium deoxycholate (0.75-2.0 mM) disrupts both zones. Subsequent incorporation of fluorine atoms into a type II substrate (aniline) results in the increase in the hydrophobicity of aniline halogenated derivatives and in changes in the substrate-binding sites for tetra- and pentafluoroanilines from the heme-iron sphere to the apoenzyme of cytochrome P-450.
I B
IB
Tsyrlov
N E
NE
Poliakova
D000818:Animals; D001665:Binding Sites; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D003840:Deoxycholic Acid / Q000494:pharmacology; D005456:Fluorescent Dyes; D066298:In Vitro Techniques; D007425:Intracellular Membranes / Q000201:enzymology / Q000378:metabolism; D008297:Male; D008563:Membrane Lipids / Q000378:metabolism*; D008862:Microsomes, Liver / Q000201:enzymology* / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013050:Spectrometry, Fluorescence; D013379:Substrate Specificity
D005456:Fluorescent Dyes; D008563:Membrane Lipids; D010743:Phospholipids; D003840:Deoxycholic Acid; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone; D003577:Cytochrome P-450 Enzyme System
Vyiavlenie razlichnykh gidrofobnykh zon mikrosomnoĭ membrany, soderzhashchikh "tochki sviazyvaniia" tsitokhroma P-450 dlia substratov tipa I i II.