Immunochemical and sub-structural characterization of sheep lung cytochrome P45OLgM2

Abstract

Sheep hmg cytochrome P45OLgM2 belonging to gene subfamily 2B, was obtained in highly purified form and antibodies against sheep lang cytochrome P45OLgM2 were produced in rabbits by uslog the previously developed methods in our laboratory. Immunolrtgical sued enzymatic studies showed that antibodies against lung cytochrome P45014M2 inhibited beazlibetamine N-demethyiadon, ethyhnorphine N-demethylation and amine 4-hydroxylation reactions In sheep lung microsomes about 99, 80 and 62%., respectively. Benzphetamine N-demethylation reaction in sheep lung microsomes was only catalyzed by cytochrome P450LgM2 isozyme while the other isozymes of P450 as well as P45OLgM2 are also involved in the metabolism of ethylmorplone and aniline. Similar to lung microsomes, benzphetamine N-demethylsae activity of the reconstituted systems containing purified sheep lung cytochrome P45K4M2 or phenobarbital (PB) treated rabbit liver cytochrome P450LM2(2B4) was also inhibited by P450LgM2 and bodies about 95 and 82%, respectively. A 50% inhibitory effect of sheep P450LgM2 andbodies was also observed in N-demethylase activity of the reconstituted system containing parified sheep lung cytochrone P450LgM2. SDS-PAGE peptide maps obtalood following the partial proteelyais of parified sheep lung cytochrome P454LgM2 and PB-rabbit Ever P450LMVB4) isoaymes, using chymotrypsin and papsin, were similar in general. However they showed some differences both qualitatively and quantitatively, suggesting that some differences exist ammo the amino acid sequences of sheep lung cytochrome P45OLgM2 and rabbit liver cytodrome P4502B4.