Evolution of the mechanism of peptidylglycine-alpha-amidating monooxygenase

标题：肽甘氨酸-α-酰胺化单加氧酶肽是一种非常小的蛋白质，由短而精确的氨基酸构建块序列组成。在复杂的多细胞生物体中，许多多肽作为信号媒介，如激素和神经递质。合成后，许多信号肽需要进一步修饰才能激活。在这个项目中，研究人员将研究几个远亲生物体中特定多肽修饰所需的酶。这项研究的目标是确定不同生物体中导致酶不同特性获得或丧失的不同结构和化学变化。确定多肽信号分子修饰这一重要步骤的机制，以及不同生物体中该机制如何变化，将指导合成修饰多肽的新方法的发展。这项工作还将有助于更好地理解不同的酶结构如何提高化学反应的效率或特异性。PI的实验室将继续努力为高中生和本科生带来科学的兴奋，重点是将未被充分代表的少数群体纳入研究计划和STEM教育。生物不同部分之间通过分泌肽进行交流是一种广泛分布的生物信号机制。这些多肽中的许多都需要在其羧基末端进行酰胺化才能发挥全部活性。这样的多肽被表达为前体，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)键的氧化断裂产生去甘氨酸酰胺化肽和乙醛。在完整的系统发育谱中，只有一种酶能催化这一反应：双功能的肽甘氨酸-α-酰胺化单加氧酶。该反应分两个阶段进行，多肽-甘氨酸-α-羟基单加氧酶对甘氨酸C(α)的羟基化反应和多肽-甘氨酸-α-酰胺化裂解酶对N-C(α)键的裂解。本项目将研究来自几个远亲生物体的肽甘氨酸-α-酰胺化单加氧酶，目的是确定它们在进化过程中何时出现，同时试图确定导致该酶的不同功能的获得或丧失的结构和化学变化，该酶对化学反应不是关键的。这项工作将使用通过X射线衍射、小角散射和对进化上遥远的生物体的蛋白质进行动力学测量而获得的结构和生化信息。

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.