Radical SAM Enzymes: Molecular Mechanisms of Radical Initiation

作者：Joan B. 5R35GM131889-02 购买快速冷冻冷却/停止流动的行政补充 项目摘要/摘要 自由基SAM是已知的最大的酶超家族之一，其成员催化 在生活的各个领域的反应都有显著的多样性。自由基SAM酶参与合成 基本辅因子和抗生素、DNA损伤的修复以及复杂生物金属的组装 在许多其他反应中，团簇。自由基SAM酶在人类和两者中的存在 有益微生物和致病微生物对理解其基本性质具有重要意义 和机械装置。拟议的研究将发展对激进的SAM机制的批判性理解， 尤其是这个庞大而多样的超家族中所有酶共同的自由基引发过程。 研究工作将集中在使用快速冷冻-淬火、冷冻还原、 退火法和光解法。然后，这些中间体将通过使用 电子顺磁共振和电子-核双谱等光谱方法 共振，以及X射线结晶学等结构方法。拟议的补编将允许 购买所需的停流混合/快速冷冻淬火和紫外可见检测能力，以 进行这些实验..

Broderick, Joan B. 5R35GM131889-02 Administrative Supplement for Purchase of a Rapid Freeze Quench / Stopped Flow Abstract/Summary of Project Radical SAM is one of the largest enzyme superfamilies known, with its members catalyzing a remarkable diversity of reactions in all domains of life. Radical SAM enzymes are involved in the synthesis of essential cofactors and antibiotics, repair of DNA damage, and the assembly of complex biological metal clusters, among many other reactions. The presence of radical SAM enzymes in humans as well as in both beneficial and pathogenic microbes lends high significance to understanding their fundamental properties and mechanisms. The proposed research will develop a critical understanding of radical SAM mechanisms, in particular the radical initiation process common to all enzymes in this large and diverse superfamily. Research efforts will focus on trapping radical intermediates using rapid freeze-quench, cryoreduction, annealing, and photolysis approaches. These intermediates will then be characterized by using spectroscopic approaches such as electron paramagnetic resonance and electron-nuclear double resonance, and structural approaches such as X-ray crystallography. The proposed supplement will allow the purchase of needed stopped-flow mixing/ rapid-freeze-quench and UV-visible detection capability to carry out these experiments..