The dimeric form of flavocytochrome P450BM3 is catalytically functional as a fatty acid hydroxylase
The dimeric form of flavocytochrome P450BM3 is catalytically functional as a fatty acid hydroxylase
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DOI：
10.1016/j.febslet.2005.09.023
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发表时间：
2005-10-24
期刊：
影响因子：
3.5
通讯作者：
Munro, AW
中科院分区：
文献类型：
--
作者：
Neeli, R;Girvan, HM;Munro, AW
在模型P450 BM 3系统中，P450在单个多肽中与其二黄素还原酶配偶体融合。BM 3在溶液中二聚化，但该现象的催化相关性是迄今为止未知的。我们发现，BM 3脂肪酸羟化酶的比活性急剧下降，在低酶浓度下，与活性二聚体分离成非活性单体。还原酶依赖的比活性在低浓度下保持或增强，表明黄素间电子转移不受影响。通过混合失活的加氧酶（A264 H）和FMN缺失（G570 D）突变体来重建脂肪酸氧化，证明单体间（FMN 1-至-血红素（2））电子转移支持BM 3二聚体中的加氧酶活性。(c)2005年由Elsevier B. V.代表欧洲生物化学学会联合会出版。
In the model P450 BM3 system, the P450 is fused to its diflavin reductase partner in a single polypeptide. BM3 dimerizes in solution, but the catalytic relevance of the phenomenon was hitherto unknown. We show that BM3 fatty acid hydroxylase specific activity decreases sharply at low enzyme concentrations, consistent with separation of active dimer into inactive monomer. Reductase-dependent specific activities are maintained or enhanced at low concentration, suggesting inter-flavin electron transfer is unaffected. Fatty acid oxidation is reconstituted by mixing inactive oxygenase (A264H) and FMN-depleted (G570D) mutants, demonstrating that inter-monomer (FMN1-to-heme(2)) electron transfer supports oxygenase activity in the BM3 dimer. (c) 2005 Published by Elsevier B.V. on behalf of the Federation of European Biochemical Societies.