期刊
SCIENCE
卷 359, 期 6381, 页码 1247-1250出版社
AMER ASSOC ADVANCEMENT SCIENCE
DOI: 10.1126/science.aao6595
关键词
-
资金
- National Institutes of Health National Institute of General Medical Sciences [GM088276, P41GM103521, P41GM103403, GM 111097, GM124908]
- NIH-ORIP HEI grant [S10 RR029205]
- DOE Office of Science [DE-AC02-06CH11357]
Diphthamide biosynthesis involves a carbon-carbon bond-forming reaction catalyzed by a radical S-adenosylmethionine (SAM) enzyme that cleaves a carbon-sulfur (C-S) bond in SAM to generate a 3-amino-3-carboxypropyl (ACP) radical. Using rapid freezing, we have captured an organometallic intermediate with an iron-carbon (Fe-C) bond between ACP and the enzyme's [4Fe-4S] cluster. In the presence of the substrate protein, elongation factor 2, this intermediate converts to an organic radical, formed by addition of the ACP radical to a histidine side chain. Crystal structures of archaeal diphthamide biosynthetic radical SAM enzymes reveal that the carbon of the SAM C-S bond being cleaved is positioned near the unique cluster Fe, able to react with the cluster. Our results explain how selective C-S bond cleavage is achieved in this radical SAM enzyme.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据