Evolution of the mechanism of peptidylglycine-alpha-amidating monooxygenase

肽基甘氨酸-α-酰胺化单加氧酶机制的演变

• 批准号: 1517522
• 负责人: L. Mario Amzel
• 金额: $ 102.87万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1517522&HistoricalAwards=false
• 关键词: Evolution; mechanism; peptidylglycine; alpha; amidating

Title: Evolution of the mechanism of peptidylglycine-alpha-amidating monooxygenase Peptides are very small proteins made up of short and precise sequences of amino acid building blocks. Many peptides serve as signaling agents such as hormones and neurotransmitters in complex multicellular organisms. After synthesis many of these signaling peptides require further modification for activation. In this project, the investigator will study the enzymes needed for a specific peptide modification from several distantly related organisms. The goal of the research is to identify different structural and chemical changes across the different organisms that resulted in the gain or the loss of different features of the enzyme. Determination of the mechanism of this important step in the modification of peptide signaling molecules and how the mechanism changes in different organisms will guide the development of new ways of producing synthetic modified peptides. The work will also lead to a better understanding of how different enzyme structures can give rise to improved efficiency or specificity for a chemical reaction. The laboratory of the PI will continue its efforts to bring the excitement of science to high school and undergraduate students with emphasis on including underrepresented minorities in the research programs and STEM education.Communication between different parts of an organism via secreted peptides is a widely distributed biological signaling mechanism. Many of these peptides require amidation at their carboxy terminus for full-activity. Such peptides are expressed as precursors that, after processing, contain a glycine residue as their last residue. Oxidative cleavage of the glycine N-C(alpha) bond produces a des-glycine amidated peptide and glyoxylate. Only one enzyme in the complete phylogenetic spectrum is known to catalyze this reaction: the bi-functional peptidylglycine-alpha-amidating monooxygenase. The reaction takes place in two stages, the hydroxylation of the glycine C(alpha) by peptidyl-glycine-alpha-hydroxylating monooxygenase, and cleavage of the N-C(alpha) bond by peptidylglycine-alpha-amidating lyase. This project will study the peptidylglycine-alpha-amidating monooxygenases from several distantly related organisms with the goal of determining when in evolution they appeared, while trying to identify the structural and chemical changes that resulted in the gain or the loss of different features of the enzyme not critical for the chemical reaction. Structural and biochemical information obtained by X-ray diffraction, small angle scattering and kinetic measurements of the proteins from evolutionarily distant organisms will be used in this work.

肽是由短而精确的氨基酸构建块序列组成的非常小的蛋白质。在复杂的多细胞生物中，许多多肽作为信号剂，如激素和神经递质。合成后，许多这些信号肽需要进一步修饰才能激活。在这个项目中，研究者将研究从几个远亲生物中获得特定肽修饰所需的酶。这项研究的目标是确定不同生物体中不同的结构和化学变化，这些变化导致酶的不同特征的增加或减少。确定肽信号分子修饰的这一重要步骤的机制以及该机制在不同生物体中的变化将指导合成修饰肽的新方法的开发。这项工作还将使人们更好地了解不同的酶结构如何提高化学反应的效率或特异性。PI实验室将继续努力，将科学的兴奋带给高中生和本科生，重点是在研究项目和STEM教育中纳入代表性不足的少数民族。生物体内不同部位之间通过分泌多肽进行通讯是一种广泛分布的生物信号传导机制。许多这些肽需要在其羧基端进行酰胺化才能完全发挥活性。这种多肽表示为前体，经过加工后，含有甘氨酸残基作为其最后残基。甘氨酸N-C（α）键的氧化裂解产生去甘氨酸酰胺肽和乙醛酸盐。在完整的系统发育谱中，已知只有一种酶能催化这一反应：双功能肽基甘氨酸-酰胺化单加氧酶。反应分两个阶段进行，肽基甘氨酸- α羟化单加氧酶羟基化甘氨酸C(α)，肽基甘氨酸- α酰胺化裂解酶裂解N-C（α）键。该项目将研究来自几个远亲生物的肽基甘氨酸- α -酰胺化单加氧酶，目的是确定它们在进化中何时出现，同时试图确定导致酶的不同特征的获得或丧失的结构和化学变化，而这些特征对化学反应并不重要。通过x射线衍射、小角散射和动力学测量获得的蛋白质结构和生化信息将用于这项工作。