ISOLATION AND CHARACTERIZATION OF A CYTOCHROME-P450 OF THE IIA SUBFAMILY FROM HUMAN LIVER-MICROSOMES

被引:74
作者
MAURICE, M
EMILIANI, S
DALETBELUCHE, I
DERANCOURT, J
LANGE, R
机构
[1] CNRS,INSERM,U128,ROUTE MENDE,BP 5051,F-34033 MONTPELLIER,FRANCE
[2] INSERM,U249,F-34100 MONTPELLIER,FRANCE
来源
EUROPEAN JOURNAL OF BIOCHEMISTRY | 1991年 / 200卷 / 02期
关键词
D O I
10.1111/j.1432-1033.1991.tb16212.x
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
Antibodies raised against cytochrome P450, which is overexpressed in mouse hepatic tumors, (P450tu) crossreact with two human liver microsomal proteins (49 kDa and 52 kDa). We have quantified these proteins in 60 human liver samples and found great interindividual variability in both of them. The concentration of the 49-kDa protein varies up to 144 fold in the various samples and represents typically 10% of the total mincrosomal P450 content. Its immunologically determined concentration correlates well (R = 0.78) with the microsomal coumarin-7-hydroylase (COH) activity. This activity is strongly and completely inhibited by anti-P450tu antibody (IC50 = 0.13 mg IgG/mg microsomal protein). The crossreacting 49-kDa protein shows an unusually high substrate specificity towards coumarin; it presents all human COH and part of 7-ethoxycoumarin O-deethylase (ECOD). Besides these two activities, we did not find any activity with other typical P450 substrates. In primary cultures of human hepatocytes, it is inducible by phenobarbital and dexamethasone, but not by pyrazole and beta-naphthoflavone. We isolated this protein from human liver microsomes and purified it to homogeneity by a combination of aminooctyl-amino-Sepharose chromatography and immunoaffinity chromatography. The protein was identified as a cytochrome P450 of the IIA subfamily. Its N-terminal amino-acid sequence was identical with the first 20 residues deduced from the nucleotide sequence of P450IIA6.
引用
收藏
页码:511 / 517
页数:7
相关论文
共 38 条
  • [1] ONTOGENY OF RABBIT LIVER CYTOCHROME-P450 - EVIDENCE FOR A CYTOCHROME-P450-IIE (3A)-RELATED FORM PREVAILING DURING THE POSTNATAL-PERIOD
    BONFILS, C
    COMBALBERT, J
    PINEAU, T
    ANGEVIN, J
    LARROQUE, C
    DERANCOURT, J
    CAPONY, JP
    MAUREL, P
    [J]. EUROPEAN JOURNAL OF BIOCHEMISTRY, 1990, 188 (01): : 187 - 194
  • [2] INDUCTION BY TRIACETYLOLEANDOMYCIN AND PARTIAL-PURIFICATION OF A LM3 FORM OF CYTOCHROME-P-450 FROM RABBIT LIVER-MICROSOMES
    BONFILS, C
    DALETBELUCHE, I
    MAUREL, P
    [J]. BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 1982, 104 (03) : 1011 - 1017
  • [3] REGULATION AND EXPRESSION OF 4 CYTOCHROME-P-450 ISOENZYMES, NADPH-CYTOCHROME-P-450 REDUCTASE, THE GLUTATHIONE TRANSFERASE-B AND TRANSFERASE-C AND MICROSOMAL EPOXIDE HYDROLASE IN PRENEOPLASTIC AND NEOPLASTIC LESIONS IN RAT-LIVER
    BUCHMANN, A
    KUHLMANN, W
    SCHWARZ, M
    KUNZ, W
    WOLF, CR
    MOLL, E
    FRIEDBERG, T
    OESCH, F
    [J]. CARCINOGENESIS, 1985, 6 (04) : 513 - 521
  • [4] BURKE MD, 1975, DRUG METAB DISPOS, V3, P245
  • [5] CAMPBELL TC, 1990, CANCER RES, V50, P6882
  • [6] A SPECTROFLUORIMETRIC STUDY OF 7-HYDROXYLATION OF COUMARIN BY LIVER MICROSOMES
    CREAVEN, PJ
    PARKE, DV
    WILLIAMS, RT
    [J]. BIOCHEMICAL JOURNAL, 1965, 96 (02) : 390 - &
  • [7] HUMAN CYTOCHROME P450IIA3 - CDNA SEQUENCE, ROLE OF THE ENZYME IN THE METABOLIC-ACTIVATION OF PROMUTAGENS, COMPARISON TO NITROSAMINE ACTIVATION BY HUMAN CYTOCHROME P450IIE1
    CRESPI, CL
    PENMAN, BW
    LEAKEY, JAE
    ARLOTTO, MP
    STARK, A
    PARKINSON, A
    TURNER, T
    STEIMEL, DT
    RUDO, K
    DAVIES, RL
    LANGENBACH, R
    [J]. CARCINOGENESIS, 1990, 11 (08) : 1293 - 1300
  • [8] CUATRECASAS P, 1970, J BIOL CHEM, V245, P3059
  • [9] DALETBELUCHE I, 1990, DRUG METABOLIZING EN, P221
  • [10] EXPRESSION OF 5 FORMS OF MICROSOMAL CYTOCHROME-P-450 IN PRIMARY CULTURES OF RABBIT HEPATOCYTES TREATED WITH VARIOUS CLASSES OF INDUCERS
    DAUJAT, M
    PICHARD, L
    DALET, C
    LARROQUE, C
    BONFILS, C
    POMPON, D
    LI, D
    GUZELIAN, PS
    MAUREL, P
    [J]. BIOCHEMICAL PHARMACOLOGY, 1987, 36 (21) : 3597 - 3606