Bandarian Vahe
University of Arizona, Department of Chemistry and Biochemistry, 1041 E. Lowell St., Tucson, AZ 85721‐0088, USA.
Biochim Biophys Acta. 2012 Nov;1824(11):1245-53. doi: 10.1016/j.bbapap.2012.07.014. Epub 2012 Aug 3.
The radical S-adenosyl-l-methionine (SAM) superfamily is a widely distributed group of iron-sulfur containing proteins that exploit the reactivity of the high energy intermediate, 5'-deoxyadenosyl radical, which is produced by the reductive cleavage of SAM, to carry-out complex radical-mediated transformations. The reactions catalyzed by radical SAM enzymes range from simple group migrations to complex reactions in protein and RNA modification. This review will highlight three radical SAM enzymes that catalyze reactions involving modified guanosines in the biosynthesis pathways of the hypermodified tRNA base wybutosine; secondary metabolites of 7-deazapurine structure, including the hypermodified tRNA base queuosine; and the redox cofactor F(420). This article is part of a Special Issue entitled: Radical SAM enzymes and Radical Enzymology.
自由基S-腺苷-L-甲硫氨酸（SAM）超家族是一类广泛分布的含铁硫蛋白，它们利用由SAM还原裂解产生的高能中间体5'-脱氧腺苷自由基的反应活性，进行复杂的自由基介导的转化。自由基SAM酶催化的反应范围从简单的基团迁移到蛋白质和RNA修饰中的复杂反应。本综述将重点介绍三种自由基SAM酶，它们在超修饰的tRNA碱基wybutosine的生物合成途径中催化涉及修饰鸟苷的反应；7-脱氮嘌呤结构的次生代谢产物，包括超修饰的tRNA碱基queuosine；以及氧化还原辅因子F(420)。本文是名为“自由基SAM酶与自由基酶学”的特刊的一部分。
