The radical S-adenosylmethionine (SAM) superfamily enzymes reductively cleave SAM to produce a highly reactive 5'-deoxyadenosyl (dAdo) radical, which in most cases abstracts a hydrogen from the substrate and initiates highly diverse reactions. In rare cases, the dAdo radical can add to a sp2 carbon to result in the production an adenosylated product. These radical SAM-dependent adenosylation reactions are present in natural product biosynthetic pathways and can be achieved by using unnatural substrate analogs containing olefin or aryl moieties. This Opinion provides a focused perspective on this emerging type of biochemistry and discusses its potential use in bioengineering and biocatalysis.

中文翻译：

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自由基S-腺苷甲硫氨酸超家族酶催化的腺苷化反应。

自由基S-腺苷甲硫氨酸（SAM）超家族酶可还原性裂解SAM，以产生高反应性5'-脱氧腺苷（dAdo）自由基，在大多数情况下，该自由基会从底物中提取氢并引发高度多样化的反应。在极少数情况下，dAdo自由基会加到sp2碳上，从而产生腺苷化产物。这些自由基SAM依赖性腺苷酸化反应存在于天然产物的生物合成途径中，可以通过使用含有烯烃或芳基部分的非天然底物类似物来实现。该意见为这种新兴的生物化学提供了集中的观点，并讨论了其在生物工程和生物催化中的潜在用途。