日本語フィールド
著者：Dong, Min; Horitani, Masaki; Dzikovski, Boris; Pandelia, Maria Eirini; Krebs, Carsten; Freed, Jack H.; Hoffman, Brian M.; Lin, Hening;題名：Organometallic Complex Formed by an Unconventional Radical S-Adenosylmethionine Enzyme発表情報：Journal of the American Chemical Society 巻: 138 号: 31 ページ: 9755-9758キーワード：概要：© 2016 American Chemical Society.Pyrococcus horikoshii Dph2 (PhDph2) is an unusual radical S-adenosylmethionine (SAM) enzyme involved in the first step of diphthamide biosynthesis. It catalyzes the reaction by cleaving SAM to generate a 3-amino-3-carboxypropyl (ACP) radical. To probe the reaction mechanism, we synthesized a SAM analogue (SAMCA), in which the ACP group of SAM is replaced with a 3-carboxyallyl group. SAMCA is cleaved by PhDph2, yielding a paramagnetic (S = 1/2) species, which is assigned to a complex formed between the reaction product, α-sulfinyl-3-butenoic acid, and the [4Fe-4S] cluster. Electron-nuclear double resonance (ENDOR) measurements with 13C and 2H isotopically labeled SAMCA support a π-complex between the C=C double bond of α-sulfinyl-3-butenoic acid and the unique iron of the [4Fe-4S] cluster. This is the first example of a radical SAM-related [4Fe-4S]+ cluster forming an organometallic complex with an alkene, shedding additional light on the mechanism of PhDph2 and expanding our current notions for the reactivity of [4Fe-4S] clusters in radical SAM enzymes.抄録：英語フィールド
Author：Dong, Min; Horitani, Masaki; Dzikovski, Boris; Pandelia, Maria Eirini; Krebs, Carsten; Freed, Jack H.; Hoffman, Brian M.; Lin, Hening; Lin, HeningTitle：Organometallic Complex Formed by an Unconventional Radical S-Adenosylmethionine EnzymeAnnouncement information:Journal of the American Chemical Society Vol: 138 Issue: 31 Page: 9755-9758An abstract：© 2016 American Chemical Society.Pyrococcus horikoshii Dph2 (PhDph2) is an unusual radical S-adenosylmethionine (SAM) enzyme involved in the first step of diphthamide biosynthesis. It catalyzes the reaction by cleaving SAM to generate a 3-amino-3-carboxypropyl (ACP) radical. To probe the reaction mechanism, we synthesized a SAM analogue (SAMCA), in which the ACP group of SAM is replaced with a 3-carboxyallyl group. SAMCA is cleaved by PhDph2, yielding a paramagnetic (S = 1/2) species, which is assigned to a complex formed between the reaction product, α-sulfinyl-3-butenoic acid, and the [4Fe-4S] cluster. Electron-nuclear double resonance (ENDOR) measurements with 13C and 2H isotopically labeled SAMCA support a π-complex between the C=C double bond of α-sulfinyl-3-butenoic acid and the unique iron of the [4Fe-4S] cluster. This is the first example of a radical SAM-related [4Fe-4S]+ cluster forming an organometallic complex with an alkene, shedding additional light on the mechanism of PhDph2 and expanding our current notions for the reactivity of [4Fe-4S] clusters in radical SAM enzymes.