Experimental Correlation of Substrate Position with Reaction Outcome in the Aliphatic Halogenase, SyrB2.
Experimental Correlation of Substrate Position with Reaction Outcome in the Aliphatic Halogenase, SyrB2.
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DOI：
10.1021/jacs.5b03370
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发表时间：
2015-06-03
影响因子：
15
通讯作者：
Silakov A
中科院分区：
文献类型：
--
作者：
Martinie RJ;Livada J;Chang WC;Green MT;Krebs C;Bollinger JM Jr;Silakov A
铁（II）和2-（氧代）戊二酸依赖性（Fe/2 OG）加氧酶催化一系列具有挑战性的转化，但酶家族的单个成员如何指导不同的结果却知之甚少。Fe/2 OG卤化酶，SyrB 2，氯化其天然底物，L-苏氨酸附加到载体蛋白质，SyrB 1的C4，但羟基化的L-正缬氨酸的C5，并在较小程度上，当SyrB 1提出这些非天然氨基酸的L-氨基丁酸的C4。为了测试的假设，定位的目标碳决定的结果，我们定义了这三个基板的位置，通过测量超精细耦合基板氘原子和稳定的，EPR活性的铁-亚硝酰加合物，反应中间体的替代品之间。Fe-2 H距离和N-Fe-2 H角从苏氨酸的4.2 °和85°变化到正缬氨酸的3.4 °和65°，使反应性的趋势合理化。这种位置与结果的实验相关性应有助于从其他Fe/2 OG酶的结构数据判断它们是否抑制羟基化或在通往其他结果的途径上形成羟基化中间体。
The iron(II)- and 2-(oxo)glutarate-dependent (Fe/2OG) oxygenases catalyze an array of challenging transformations, but how individual members of the enzyme family direct different outcomes is poorly understood. The Fe/2OG halogenase, SyrB2, chlorinates C4 of its native substrate, L-threonine appended to the carrier protein, SyrB1, but hydroxylates C5 of L-norvaline and, to a lesser extent, C4 of L-aminobutyric acid when SyrB1 presents these non-native amino acids. To test the hypothesis that positioning of the targeted carbon dictates the outcome, we defined the positions of these three substrates by measuring hyperfine couplings between substrate deuterium atoms and the stable, EPR-active iron-nitrosyl adduct, a surrogate for reaction intermediates. The Fe-2H distances and N-Fe-2H angles, which vary from 4.2 Å and 85° for threonine to 3.4 Å and 65° for norvaline, rationalize the trends in reactivity. This experimental correlation of position to outcome should aid in judging from structural data on other Fe/2OG enzymes whether they suppress hydroxylation or form hydroxylated intermediates on the pathways to other outcomes.
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影响因子：
56.9
作者：
Jaakkola, P;Mole, DR;Ratcliffe, PJ
通讯作者：
Ratcliffe, PJ
影响因子：
7.8
作者：
Booker, Squire J.
通讯作者：
Booker, Squire J.
DOI：
10.1021/jp404743d
发表时间：
2013-09-12
期刊：
The journal of physical chemistry. B
影响因子：
--
作者：
Casey TM;Grzyska PK;Hausinger RP;McCracken J
通讯作者：
McCracken J
影响因子：
7.8
作者：
Krebs, Carsten;Bollinger, J. Martin, Jr.;Booker, Squire J.
通讯作者：
Booker, Squire J.
DOI：
10.1126/science.1151710
发表时间：
2007-11-30
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Gerken T;Girard CA;Tung YC;Webby CJ;Saudek V;Hewitson KS;Yeo GS;McDonough MA;Cunliffe S;McNeill LA;Galvanovskis J;Rorsman P;Robins P;Prieur X;Coll AP;Ma M;Jovanovic Z;Farooqi IS;Sedgwick B;Barroso I;Lindahl T;Ponting CP;Ashcroft FM;O'Rahilly S;Schofield CJ
通讯作者：
Schofield CJ