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Updated: Jul 23, 2025

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激进SAM酶中的分子间电子转移作为减少激活的新范式

Karsten A S Eastman¹, Andrew S Jochimsen¹, Vahe Bandarian¹

¹University of Utah, Department of Chemistry, Salt Lake City, Utah, USA.

The Journal of biological chemistry

|July 17, 2023

概括

激进的S-adenosyl-L-methionine (rSAM) 酶利用辅助的铁硫集群 (ACs) 进行催化. 这项研究表明,ACs调解分子间电子转移,这对于rSAM酶激活和天然产品生物合成至关重要.

科学领域:

生物化学生物化学
酶学是一种酶学.
自然产品生物合成自然产品生物合成

背景情况:

激进的S-adenosyl-L-methionine (rSAM) 酶对于合成复杂的自然产品至关重要.
这些酶利用铁硫 (Fe-S) 集群进行催化,辅助集群 (ACs) 的功能基本上是未知的.
rSAM酶PapB在PapA中形成了铁交叉链接.

研究的目的:

阐明辅助Fe-S集群在rSAM酶激活和催化中的作用.
为了研究PapB酶中电子状态异构的机制.
探索 rSAM 酶功能的分子间电子转移的潜力.

主要方法:

构建和分析PapB酶的铁硫删除突变体.
生物化学测定用于监测酶活性和电子转移.
对酶周转的辅因子要求的研究.

主要成果:

在PapB中的一个AC与基质结合,并在 thioether 键形成过程中接受降解等价物.
电子状态异构化需要分子间电子转移,可能由第二个交流电介导.
一种FMN和NADPH的混合物可以支持还原性裂变和异构化步骤.

结论:

rSAM酶激活涉及辅助Fe-S集群介导的分子间电子转移步骤.
这一发现为多集群rSAM酶的生物激活提供了一个新的范式.
这些结果对理解天然产品生物合成和酶机制具有重大意义.

关键词:

这是一种S-adenosyl-L-methionine (SAM) 的类型.电子转移是电子的转移.酶激活的酶激活方式酶机制的酶机制是什么铁硫蛋白质是一种铁硫蛋白质.激进的SAM SAM是一种激进的SAM.

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