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Mechanisms of Catalysis and Cofactor Biosynthesis of Redox Enzymes with Unusual Cofactors

具有异常辅因子的氧化还原酶的催化和辅因子生物合成机制

基本信息

批准号：
10544716
负责人：
VICTOR L DAVIDSON
金额：
$ 40.12万
依托单位：
UNIVERSITY OF CENTRAL FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-01-01 至 2023-07-31
项目状态：
已结题

项目摘要

This research program focuses on the characterization of redox enzymes with unusual cofactors, and their interactions with other electron transfer (ET) proteins. This includes enzymes that do not contain exogenous cofactors, but instead possess “protein-derived cofactors” that are formed by multiple irreversible post-translational modifications of amino acid residues. This research has made major contributions to at least three areas of broad biological and biomedical significance: elucidation of mechanisms of biological ET; characterization of mechanisms of biosynthesis of protein-derived cofactors and their catalytic properties; and discovery of novel mechanisms of heme function and oxygen activation. The future goals include characterization of three novel classes of redox enzymes that we have recently identified. Lod-A like proteins possess a cysteine tryptophylquinone (CTQ) cofactor derived from specific cysteine and tryptophan residues. These are unusual as they are the first enzymes with tryptophylquinone cofactors that function as oxidases rather than dehydrogenases. They are also the first amino acid oxidases described that uses a cofactor other than a flavin for catalysis. LodB-like proteins are flavoenzymes that catalyze the post-translational modifications required for CTQ biosynthesis on a precursor LodA-like protein. These reactions must be performed by “remote catalysis” that involves long-range ET, since the residues that are modified reside within the protein and are not surface exposed. As such, the mechanism of this process must be novel because no such reactions have been described that are catalyzed by a flavoenzyme, especially by remote catalysis. Rv2633c is a protein from Mycobacterium tuberculosis that is upregulated in response to the host defense during infection. It possesses two non-heme irons that are predicted from sequence to form an oxo-bridged hemerythrin-like site. We showed that this is the first hemerythrin-like protein to function as a catalase, and is the first example of a catalase with a non-heme di-iron cofactor. The results of these studies will further our understanding of the range and mechanisms of reactions that can be catalyzed by enzymes, particularly those involving oxygen reactivity and free radical intermediates. Understanding how enzymes control these reactive species during catalysis while minimizing oxidative damage will provide insights into how to mitigate the consequences of oxidative stress. This will also expand or current views about protein evolution and protein structure-function relationships, and provide insights for protein engineering strategies to introduce new functional groups into proteins.

该研究计划的重点是具有不寻常特征的氧化还原酶的表征辅因子，以及它们与其他电子转移（ET）蛋白的相互作用。这包括不含外源辅因子，但具有“蛋白质衍生酶”的酶由氨基酸的多个不可逆翻译后修饰形成的辅因子” 残留物。这项研究至少对广泛的生物学三个领域做出了重大贡献生物医学意义：阐明生物ET的机制；的表征蛋白质辅助因子的生物合成机制及其催化特性；和发现血红素功能和氧活化的新机制。未来的目标包括我们最近发现的三类新型氧化还原酶的表征确定。 Lod-A 样蛋白具有半胱氨酸色氨酸醌 (CTQ) 辅因子，源自特定的半胱氨酸和色氨酸残基。这些酶很不寻常，因为它们是第一种具有色氨酸醌辅助因子，作为氧化酶而不是脱氢酶发挥作用。他们是也是第一个描述的使用黄素以外的辅因子进行催化的氨基酸氧化酶。 LodB 样蛋白是催化所需翻译后修饰的黄素酶用于前体 LodA 样蛋白的 CTQ 生物合成。这些反应必须由 “远程催化”涉及长程 ET，因为被修饰的残基位于蛋白质并且没有表面暴露。因此，这个过程的机制必须是新颖的因为没有描述过由黄素酶催化的此类反应，特别是通过远程催化。 Rv2633c 是一种来自结核分枝杆菌的蛋白质，感染期间响应宿主防御而上调。它拥有两种非血红素铁根据序列预测它们会形成氧桥血红蛋白样位点。我们证明了这是第一个具有过氧化氢酶功能的类血红蛋白蛋白，也是第一个例子具有非血红素二铁辅因子的过氧化氢酶。这些研究的结果将进一步推动我们了解酶催化反应的范围和机制，特别是涉及氧反应性和自由基中间体的那些。了解如何酶在催化过程中控制这些活性物质，同时最大限度地减少氧化损伤提供有关如何减轻氧化应激后果的见解。这也将扩大或关于蛋白质进化和蛋白质结构-功能关系的当前观点，并提供对将新功能基团引入蛋白质的蛋白质工程策略的见解。

项目成果

期刊论文数量（10）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Characterization of PlGoxB, a flavoprotein required for cysteine tryptophylquinone biosynthesis in glycine oxidase from Pseudoalteromonas luteoviolacea.

PlGoxB 的表征，PlGoxB 是黄黄假交替单胞菌甘氨酸氧化酶中半胱氨酸色氨酸醌生物合成所需的黄素蛋白。

DOI：
10.1016/j.abb.2019.108110
发表时间：
2019
期刊：
Archives of biochemistry and biophysics
影响因子：
3.9
作者：
Mamounis,KyleJ;Ma,Zhongxin;Sanchez-Amat,Antonio;Davidson,VictorL
通讯作者：
Davidson,VictorL

The hemerythrin-like diiron protein from Mycobacterium kansasii is a nitric oxide peroxidase.

DOI：
10.1016/j.jbc.2022.101696
发表时间：
2022-03
期刊：
The Journal of biological chemistry
影响因子：
0
作者：
Ma Z;Holland AA;Szlamkowicz I;Anagnostopoulos V;Caldas Nogueira ML;Caranto JD;Davidson VL
通讯作者：
Davidson VL

Structural Determinants of the Specific Activities of an L-Amino Acid Oxidase from Pseudoalteromonas luteoviolacea CPMOR-1 with Broad Substrate Specificity.

DOI：
10.3390/molecules27154726
发表时间：
2022-07-24
期刊：
MOLECULES
影响因子：
4.6
作者：
Mamounis, Kyle J.;Nogueira, Maria Luiza Caldas;Salvador, Daniela Priscila Marchi;Andreo-Vidal, Andres;Sanchez-Amat, Antonio;Davidson, Victor L.
通讯作者：
Davidson, Victor L.

Substitution of the sole tryptophan of the cupredoxin, amicyanin, with 5-hydroxytryptophan alters fluorescence properties and energy transfer to the type 1 copper site.

DOI：
10.1016/j.jinorgbio.2022.111895
发表时间：
2022-09
期刊：
JOURNAL OF INORGANIC BIOCHEMISTRY
影响因子：
3.9
作者：
Pastore, Anthony J.;Ficaretta, Elise;Chatterjee, Abhishek;Davidson, Victor L.
通讯作者：
Davidson, Victor L.

Diversity of structures and functions of oxo-bridged non-heme diiron proteins.