Complete amino acid sequence and predicted membrane topology of phenobarbital-induced cytochrome P-450 (isozyme 2) from rabbit liver microsomes.
Complete amino acid sequence and predicted membrane topology of phenobarbital-induced cytochrome P-450 (isozyme 2) from rabbit liver microsomes.
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来自兔肝微粒体的苯巴比妥诱导的细胞色素 P-450（同工酶 2）的完整氨基酸序列和预测的膜拓扑结构。
DOI：
10.1073/pnas.80.21.6552
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发表时间：
1983
影响因子：
11.1
通讯作者：
Coon,MJ
中科院分区：
文献类型：
--
作者：
Tarr,GE;Black,SD;Fujita,VS;Coon,MJ
给出了苯巴比妥诱导的兔肝微粒体细胞色素P-450同工酶2（P-450 LM 2）的完整氨基酸序列。该多肽由491个残基组成，计算的Mr为55，755。兔同工酶是77%相同的相应的大鼠细胞色素，P-450 b，推导出的cDNA，96%的疏水性，88%的阴离子，和83%的阳离子的位置保守。预测了同工酶2的二级结构，并建立了该细胞色素的膜拓扑结构模型。在P-450 LM 2、P-450 b和细菌P-450 cam中的两个高度保守的半胱氨酰肽中，基于我们的模型，我们倾向于更靠近NH 2末端的一个（P-450 LM 2中的Cys-152）作为血红素铁原子的巯基配体的来源。最近报道的明显相同的蛋白质的序列[Heinemann，F. S.和Ozols，J.（1983）J.Biol.Chem.258，4195-4201]具有少两个残基并且在14个其它氨基酸分配中不同。
The complete amino acid sequence of phenobarbital-induced isozyme 2 of rabbit liver microsomal cytochrome P-450 (P-450LM2) is presented. The polypeptide consists of 491 residues with a calculated Mr of 55,755. The rabbit isozyme is 77% identical to the corresponding rat cytochrome, P-450b, as deduced from cDNA, with 96% of the hydrophobic, 88% of the anionic, and 83% of the cationic positions conserved. The secondary structure of isozyme 2 was predicted and a model was developed for the membrane topology of this cytochrome. Of the two highly conserved cysteinyl peptides in P-450LM2, P-450b, and bacterial P-450cam, we favor, on the basis of our model, the one nearer the NH2 terminus (Cys-152 in P-450LM2) as the source of the thiolate ligand to the heme iron atom. The recently reported sequence of the apparently identical protein [Heinemann, F. S. & Ozols, J. (1983) J. Biol. Chem. 258, 4195-4201] has two fewer residues and differs in 14 other amino acid assignments.