As the field of radical SAM enzymology has grown from a few examples in the 1990s to hundreds of thousands today, a fundamental question has remained: how does Nature use S-adenosyl-L-methionine to initiate radical reactions? This was a driving question when we first began studying pyruvate formate-lyase activating enzyme in 1993, and our journey for answers has brought us to many surprising discoveries, from the direct coordination of SAM to a unique iron in a [4Fe-4S] cluster, to our recent discovery of an organometallic intermediate and our ability to quantitatively produce and characterize the long-sought 5'-deoxyadenosyl radical intermediate. These adventures and what we have learned along the way about this fundamentally novel chemistry is described in this review.

中文翻译：

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自由基 SAM 酶：理解机制的过程中的惊喜。

随着激进 SAM 酶学领域从 1990 年代的几个例子发展到今天的数十万，一个基本问题仍然存在：大自然如何使用 S-腺苷-L-蛋氨酸来引发自由基反应？当我们在 1993 年第一次开始研究丙酮酸甲酸裂合酶激活酶时，这是一个驱动性问题，我们寻求答案的旅程给我们带来了许多令人惊讶的发现，从 SAM 的直接配位到 [4Fe-4S] 簇中的独特铁，我们最近发现了一种有机金属中间体，以及我们定量生产和表征长期寻找的 5'-脱氧腺苷自由基中间体的能力。这篇评论描述了这些冒险以及我们在此过程中学到的关于这种基本新颖的化学的知识。