From Fundamental Studies of Metalloproteins to Practical Applications

从金属蛋白的基础研究到实际应用

• 批准号: 10580467
• 负责人: OLGA MAKHLYNETS
• 金额: $ 32.81万
• 依托单位: SYRACUSE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-15 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10580467
• 关键词: Active Sites; Address; Affinity; Binding; Biological; Chemical Weapons; Chemicals; Consensus; Cysteine; Defense Mechanisms; Development; Environment; Enzymes; Evolution; Family; Genes; Human; Human Activities; Hydrogen Peroxide; Ions; Iron; Lignin; Manganese; Metalloproteins; Metals; Methane; Methanol; Modeling; Molecular; Nature; Nucleotides; Nutritional; Organism; Oxidants; Oxidation-Reduction; Oxides; Oxygen; Pathogenicity; Pathway interactions; Pesticides; Phenols; Pneumonia; Process; Property; Protein Family; Proteins; Reaction; Reporting; Ribonucleotide Reductase; Scaffolding Protein; Site; Starvation; Streptococcus sanguis; Structure; Structure-Activity Relationship; Study models; System; Testing; Time; Work; biomaterial compatibility; catalyst; chemical reaction; cofactor; depolymerization; design; experimental study; extracellular; fascinate; human pathogen; improved; insight; metalloenzyme; oxidation; practical application; preference; protein function; rational design; remediation; response; sensor; undergraduate student; uptake

Metalloenzymes are capable of efficiently tuning the properties of a metal ion to catalyze very difficult chemical transformations. Yet the determinants of what guides the evolution of protein function still remain not fully understood. This lack of understanding of the subtle detail of interactions that determine enzymatic function limits our ability to rationally design catalysts. We will test why the same family of enzymes uses different metallocofactors. Metalloenzyme NrdF belongs to a class of ribonucleotide reductases (RNR), essential enzymes found in all organisms to catalyze the conversion of nucleotides to deoxynucleotides. RNRs rely on metals to oxidize a conserved cysteine in the active site into a thiyl radical, which then initiates nucleotide reduction. Several different classes of RNRs have been identified in various organisms and, interestingly, despite a remarkable conservation of the overall catalytic pathway, the enzyme can utilize different metals to achieve it. We have recently shown that dimanganese center in class Ib RNRs of pathogenic organisms performs the same task as the diiron center in humans. Moreover, other class I RNR enzymes utilize diiron and mixed iron- manganese centers for function. The molecular and biological determinants of this metal preference still remain unknown and present a major unanswered question in the field. To address this question, we devised three specific aims. Aim 1. Elucidation of the origins of specific metalation in RNR. Using class Ib RNR from Streptococcus sanguinis (Ss) we will address the fundamental question of how correct metalation of enzymes is controlled. Aim 2. Design of functional RNR models. We will use a stable and simple protein model of RNR (DFsc) to bind various metal ions and generate catalysts for practically useful reactions. This aim will give simple, inexpensive and biocompatible protein catalysts for redox transformations and pesticide/chemical weapons remediation in the environment, that could be easily handled in the applied setting. Aim 3. Structural characterization of metalloproteins. Here we will test how metal ions influence the structure of the protein. The work proposed in this aim will validate and correlate the studies on the natural enzymes.

金属酶能够有效地调节金属离子的性质，以催化非常困难的化学反应。 转变然而，指导蛋白质功能进化的决定因素仍然不完全 明白这种对决定酶功能限制的相互作用的微妙细节的缺乏理解 我们合理设计催化剂的能力。我们将测试为什么相同的酶家族使用不同的 金属辅因子金属酶NrdF属于一类核糖核苷酸还原酶（RNR），必需的 在所有有机体中发现的催化核苷酸转化为脱氧核苷酸的酶。RNR依赖于 金属将活性位点中的保守半胱氨酸氧化成硫酰基自由基，然后引发核苷酸 还原已经在各种生物体中鉴定出几种不同类型的RNR，有趣的是，尽管 由于整个催化途径的显著保守性，酶可以利用不同的金属来实现它。 我们最近已经表明，在致病生物体的Ib类RNR中的二锰中心执行相同的功能， 作为人类的二铁中心。此外，其他I类RNR酶利用二铁和混合铁- 锰中心的功能。这种金属偏好的分子和生物学决定因素仍然是 仍然是未知的，并提出了一个重大的悬而未决的问题，在外地。为了解决这个问题，我们 提出了三个具体目标。目标1。RNR中特定金属化起源的阐明。使用Ib类 RNR从血链球菌（Ss），我们将解决如何正确的金属化的基本问题， 酶是可控的。目标2.功能RNR模型的设计。我们将使用一个稳定而简单的蛋白质模型 的RNR（DFsc）结合各种金属离子并产生用于实际有用的反应的催化剂。这一目标将 提供简单、廉价和生物相容的蛋白质催化剂，用于氧化还原转化和农药/化学品 环境中的武器补救，这在应用环境中可以很容易地处理。目标3.结构 金属蛋白的表征。在这里，我们将测试金属离子如何影响蛋白质的结构。 在这个目标中提出的工作将验证和相关的天然酶的研究。