Structure/Function of Mn and Fe Superoxide Dismutases and Related Enzymes

Mn和Fe超氧化物歧化酶及相关酶的结构/功能

• 批准号: 7996026
• 负责人: Thomas Christian Brunold
• 金额: $ 24.57万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-06-05 至 2012-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7996026
• 关键词: Active Sites; Address; Aerobic; Alzheimer' s Disease; Amino Acids; Anions; Cell Respiration; Complex; Cysteine; Cysteine dioxygenase; Dioxygenases; Electronics; Engineering; Environment; Enzymes; Escherichia coli; Excision; Family; Funding; Goals; Hydrogen Peroxide; Ions; Iron; Iron Superoxide Dismutase; Knowledge; Light; Manganese Superoxide Dismutase; Metal Ion Binding; Metals; Mind; Molecular; Motor Neuron Disease; Names; Nature; Neurodegenerative Disorders; Nickel; Organism; Oxidation-Reduction; Oxygen; Parkinson Disease; Pharmacologic Substance; Photosynthesis; Play; Positioning Attribute; Principal Investigator; Property; Proteins; Reaction; Reactive Oxygen Species; Research; Rest; Role; Scaffolding Protein; Side; Structure; Structure-Activity Relationship; Superoxide Dismutase; Superoxides; Testing; Water; analog; base; cofactor; cysteine sulfinic acid; design; enzyme mechanism; insight; member; metalloenzyme; mutant; novel; nutrition; oxidation; programs; protein folding

DESCRIPTION (provided by applicant): Molecular oxygen is utilized by aerobic organisms to perform a variety of demanding oxidative transformations, such as the conversion of cysteine to cysteine sulfinic acid catalyzed by cysteine dioxygenase (CDO). However, aerobic metabolism also leads to various side reactions that produce reactive oxygen species, such as the superoxide anion (O2-). Nature has therefore developed an effective strategy for O2- removal that involves metalloenzymes known as superoxide dismutases (SODs), which require either Fe, Mn, Cu/Zn, or Ni metal cofactors for catalytic activity. Found in all aerobic organisms, SODs disproportionate the superoxide radical to O2 and H2O2. The Long-Term Objectives of the research outlined in this proposal are: 7 To identify key geometric and electronic structural features of the Fe- and MnSODs that contribute to the high catalytic rates of these enzymes. 7 To obtain molecular level insight into the reaction mechanisms of SODs and CDO. 7 To utilize our knowledge for engineering novel enzymatic functions into FeSOD. With these goals in mind, we have formulated the following Specific Aims: 1. Elucidate the mechanism of long-range tuning of the active site properties in Fe- and MnSODs. 2. Explore the means by which the so-called cambialistic SODs overcome the challenge of providing an active-site environment that tolerates both Fe- and Mn-supported activity. 3. Obtain molecular-level insight into the catalytic mechanisms of Fe- and MnSODs. 4. Identify key structural elements for Ni-supported SOD activity. 5. Investigate structure/function relationships and the catalytic mechanism of CDO. 6. Engineer CDO activity into FeSOD. To accomplish these goals, we will use a combined spectroscopic/computational approach for studying the resting states and substrate (analog) complexes of the native enzymes and selected mutants. The Fe- and MnSODs provide almost ideal protein scaffolds for investigating the mechanisms of long- range tuning of active-site properties, such as the metal ion reduction potential and substrate (analog)/active site interactions. By extending our studies to NiSOD and CDO, we can test and refine our hypotheses regarding the principles by which outer-sphere amino acid residues contribute to the optimization of metalloenzyme active sites. From a practical point of view, insights gained in our proposed studies may provide the basis for the rational design of SOD and CDO mimics for pharmaceutical applications, such as the treatment of Alzheimer disease and Parkinson disease. Both the superoxide radical anion and free cysteine have been shown to play a role in several neurodegenerative diseases, including motor neuron disease, Parkinson disease, and Alzheimer disease. Under normal circumstances, the concentration of these species is maintained at very low levels by superoxide dismutases and cysteine dioxygenase, which are the focus of this proposal. Insights gained in our proposed studies may provide a suitable basis for the rational design of enzyme mimics for pharmaceutical applications, such as the treatment of neurodegenerative diseases.

描述（由申请人提供）：需氧生物利用分子氧来执行各种要求较高的氧化转化，例如半胱氨酸双加氧酶（CDO）催化的半胱氨酸转化为半胱氨酸亚磺酸。然而，有氧代谢也会导致各种副反应，产生活性氧，例如超氧阴离子（O2-）。因此，大自然开发了一种有效的除氧策略，其中涉及称为超氧化物歧化酶（SOD）的金属酶，其需要铁、锰、铜/锌或镍金属辅助因子来发挥催化活性。 SOD 存在于所有需氧生物中，可将超氧自由基歧化为 O2 和 H2O2。该提案中概述的研究的长期目标是： 7 确定有助于这些酶的高催化速率的 Fe 和 MnSOD 的关键几何和电子结构特征。 7 获得对 SOD 和 CDO 反应机制的分子水平洞察。 7 利用我们的知识将新的酶功能转化为 FeSOD。考虑到这些目标，我们制定了以下具体目标： 1. 阐明 Fe- 和 MnSOD 活性位点特性的远程调节机制。 2. 探索所谓的形成层 SOD 克服提供耐受 Fe 和 Mn 支持活性的活性位点环境的挑战的方法。 3. 在分子水平上深入了解 Fe- 和 MnSOD 的催化机制。 4. 确定 Ni 支持的 SOD 活性的关键结构元件。 5. 研究CDO的结构/功能关系和催化机制。 6. 将 CDO 活性设计成 FeSOD。为了实现这些目标，我们将使用组合的光谱/计算方法来研究天然酶和选定突变体的静息状态和底物（模拟）复合物。 Fe-和 MnSOD 为研究活性位点特性的远程调节机制提供了几乎理想的蛋白质支架，例如金属离子还原电位和底物（模拟）/活性位点相互作用。通过将我们的研究扩展到 NiSOD 和 CDO，我们可以测试和完善我们关于外球氨基酸残基有助于金属酶活性位点优化的原理的假设。从实践的角度来看，我们提出的研究中获得的见解可能为合理设计 SOD 和 CDO 模拟物的药物应用（例如治疗阿尔茨海默病和帕金森病）提供基础。超氧自由基阴离子和游离半胱氨酸已被证明在多种神经退行性疾病中发挥作用，包括运动神经元病、帕金森病和阿尔茨海默病。在正常情况下，这些物质的浓度通过超氧化物歧化酶和半胱氨酸双加氧酶维持在非常低的水平，这是本提案的重点。在我们提出的研究中获得的见解可能为药物应用（例如神经退行性疾病的治疗）的酶模拟物的合理设计提供合适的基础。

项目成果

How can a single second sphere amino acid substitution cause reduction midpoint potential changes of hundreds of millivolts?

• DOI: 10.1021/ja069224t
• 发表时间: 2007-08-15
• 期刊: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
• 影响因子: 15
• 作者: Yikilmaz, Emine;Porta, Jason;Miller, Anne-Frances
• 通讯作者: Miller, Anne-Frances

Spectroscopic and computational studies of a series of high-spin Ni(II) thiolate complexes.

一系列高自旋 Ni(II) 硫醇络合物的光谱和计算研究。

• DOI: 10.1021/ic100362q
• 发表时间: 2010
• 期刊: Inorganic chemistry
• 影响因子: 4.6
• 作者: VanHeuvelen,KatherineM;Cho,Jaeheung;Dingee,Timothy;Riordan,CharlesG;Brunold,ThomasC
• 通讯作者: Brunold,ThomasC

Spectroscopic and computational studies of a small-molecule functional mimic of iron superoxide dismutase, iron 2,6-diacetylpyridinebis(semioxamazide).

铁超氧化物歧化酶小分子功能模拟物铁 2,6-二乙酰吡啶双（半恶嗪）的光谱和计算研究。

• DOI: 10.1021/ic301547z
• 发表时间: 2012
• 期刊: Inorganic chemistry
• 影响因子: 4.6
• 作者: Gutman,CraigT;Brunold,ThomasC
• 通讯作者: Brunold,ThomasC

Geometric and electronic structures of manganese-substituted iron superoxide dismutase.

锰取代的铁超氧化物歧化酶的几何和电子结构。

• DOI: 10.1021/ic302867y
• 发表时间: 2013
• 期刊: Inorganic chemistry
• 影响因子: 4.6
• 作者: Jackson,TimothyA;Gutman,CraigT;Maliekal,James;Miller,Anne-Frances;Brunold,ThomasC
• 通讯作者: Brunold,ThomasC

Spectroscopic and computational insights into second-sphere amino-acid tuning of substrate analogue/active-site interactions in iron(III) superoxide dismutase.

对铁（III）超氧化物歧化酶中底物类似物/活性位点相互作用的第二球氨基酸调节的光谱和计算见解。

• DOI: 10.1021/ic702414m
• 发表时间: 2008
• 期刊: Inorganic chemistry
• 影响因子: 4.6
• 作者: Grove,LaurieE;Xie,Juan;Yikilmaz,Emine;Karapetyan,Anush;Miller,Anne-Frances;Brunold,ThomasC
• 通讯作者: Brunold,ThomasC