The roles of individual amino acids in altering substrate specificity of the P450 2a4/2a5 enzymes

被引:19
作者
Negishi, M [1 ]
Uno, T [1 ]
Honkakoski, P [1 ]
Sueyoshi, T [1 ]
Darden, TA [1 ]
Pedersen, LP [1 ]
机构
[1] NIEHS, LAB QUANTITAT & COMPUTAT BIOL, NIH, RES TRIANGLE PK, NC 27709 USA
关键词
P450; substrate specificity; site-directed mutagenesis; computer modeling;
D O I
10.1016/S0300-9084(97)82525-4
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
A single amino acid substitution is sufficient to alter substrate specificity of P450 enzymes. Mouse P450 2a5, for example, has its substrate specificity converted from coumarin 7- to testosterone 15 alpha-hydroxylase activity by the substitution of Phe at position 209 to Leu. Furthermore, placing Asn at this position confers a novel corticosterone 15 alpha-hydroxylase activity to this P450. Recent site-directed mutational studies show the presence of the topologically common residues, each of which can determine the specificities of various mammalian P450s. For instance, residue 209 (in 2a5) corresponds to a residue at position 206 in rat P4502B1 that regulates its steroid hydroxylase activity. High substrate specificity often observed in an individual P450, therefore, can be determined and altered by the identities of a few critical residues. The structural flexibility of the substrate-heme pocket may also provide P450 enzymes with the ability to display a broad range of substrate specificities. Understanding the underlying principles whereby the flexible pocket determines P450 activities may lead us to the prediction of P450 activities based on the identities of key amino acid residues.
引用
收藏
页码:685 / 694
页数:10
相关论文
共 40 条
[1]   LACK OF THE STEROID 15-ALPHA-HYDROXYLASE GENE (CYP2A-4) IN WILD MOUSE STRAIN MUS-SPRETUS - RAPID EVOLUTION OF THE P450 GENE SUPERFAMILY [J].
AIDA, K ;
MOORE, R ;
NEGISHI, M .
GENOMICS, 1994, 19 (03) :564-566
[2]  
GOTOH O, 1992, J BIOL CHEM, V267, P83
[3]  
HALPERT JR, 1993, J BIOL CHEM, V268, P4453
[4]   STRUCTURE AND FUNCTION OF CYTOCHROMES-P450 - A COMPARATIVE-ANALYSIS OF 3 CRYSTAL-STRUCTURES [J].
HASEMANN, CA ;
KURUMBAIL, RG ;
BODDUPALLI, SS ;
PETERSON, JA ;
DEISENHOFER, J .
STRUCTURE, 1995, 3 (01) :41-62
[5]   ROLE OF RESIDUE-478 AS A DETERMINANT OF THE SUBSTRATE-SPECIFICITY OF CYTOCHROME-P450-2B1 [J].
HE, YA ;
BALFOUR, CA ;
KEDZIE, KM ;
HALPERT, JR .
BIOCHEMISTRY, 1992, 31 (38) :9220-9226
[6]   Structure of the multifunctional loops in the nonclassical ATP-binding fold of glutathione synthetase [J].
Hibi, T ;
Nishioka, T ;
Kato, H ;
Tanizawa, K ;
Fukui, T ;
Katsube, Y ;
Oda, J .
NATURE STRUCTURAL BIOLOGY, 1996, 3 (01) :16-18
[7]  
HSU MH, 1993, J BIOL CHEM, V268, P6939
[8]  
IWASAKI M, 1994, J BIOL CHEM, V269, P9079
[9]   MULTIPLE STEROID-BINDING ORIENTATIONS - ALTERATION OF REGIOSPECIFICITY OF DEHYDROEPIANDROSTERONE 2-HYDROXYLASE AND 7-HYDROXYLASE ACTIVITIES OF CYTOCHROME-P-450-2A-5 BY MUTATION OF RESIDUE-209 [J].
IWASAKI, M ;
DAVIS, DG ;
DARDEN, TA ;
PEDERSEN, LG ;
NEGISHI, M .
BIOCHEMICAL JOURNAL, 1995, 306 :29-33
[10]  
IWASAKI M, 1993, J BIOL CHEM, V268, P759