CAREER: Secondary Amine Selective Petasis (SASP) Bioconjugation

有了这个奖项，化学部的生命过程化学项目正在资助奥本大学的Monika Raj博士开发一种化学方法，该方法可以在其他类似位点的海洋中选择性地标记生物分子上的特定位点。 在这种情况下，已知特异性标记的位点“打开”或“关闭”细胞内负责细胞生长的非常重要的功能，以及从一个细胞到另一个细胞的信息传递。 该提案旨在使用新的化学标记方法更好地了解反应位点的生物学意义，即它们如何控制细胞功能。 Raj博士开发了基于经典化学反应的创新应用的方法，用于可视化生物分子并用染料标记它们。 该项目还支持继续努力增加科学领域的多样性，允许来自代表性不足的少数民族的研究生和本科生获得有机化学和生物化学方面的培训。外联活动吸引高中生（特别是女性和代表性不足的少数群体），通过有趣的实验让他们接触基本的科学概念，最终鼓励他们在STEM领域从事研究和学术事业。在蛋白质表面存在反应性氨基酸侧链的情况下，可以在单一位点靶向特定官能团的化学策略是有限的。更罕见的是有机反应，可以在足够温和的条件下进行标记生物分子。为了应对这些挑战，本研究项目开发了一种新的多组分生物缀合方法，该方法基于经典的有机Petasis反应，用于选择性标记含有仲胺的蛋白质。该方法用于标记具有各种货物的蛋白质上含有翻译后修饰（PTM）的单甲基赖氨酸。这些单甲基赖氨酸PTMs的失调与各种不同的生物学功能障碍有关，但仍然缺乏选择性检测单甲基赖氨酸PTMs的化学方法。这项研究提供了一种高度选择性的化学工具，可以有效地检测单甲基赖氨酸PTM，这些PTM不仅存在于组蛋白蛋白上，而且存在于其他蛋白质上，并决定了各种蛋白质-蛋白质相互作用和功能。因此，拟议的研究有很大的潜力，以进一步了解这些PTM如何调节各种细胞信号传导过程和PTM本身是如何调节的。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Dr. Monika Raj from Auburn University to develop a chemical method that can selectively label a specific site on a biomolecule in the presence of sea of other similar sites. In this case, the specifically labeled site is known to "turn on" or "turn off" very important functions inside the cell which are responsible for cell growth, as well as the transfer of information from one cell to another. The proposal aims to use the new chemical labeling method to better understand the biological significance of the reactive sites, that is how they control cellular function. Dr. Raj develops methods based on innovative applications of classical chemical reactions for visualizing biomolecules and tagging them with dye. This project also supports continued efforts toward increasing diversity in science fields by allowing graduate and undergraduate students from underrepresented minorities to gain training in both organic chemistry and biochemistry. Outreach activities engage high school students (especially women and underrepresented minorities) and expose them to basic concepts of science through fun experimentation, ultimately encouraging them to pursue studies and academic careers in STEM fields.Chemical strategies that can target a particular functional group at a single site in the presence of reactive amino acid side chains on protein surfaces are limited. Even more rare are organic reactions that can proceed under conditions mild enough to label biomolecules. To address these challenges, this research project develops a new multicomponent bioconjugation method based on the classical organic Petasis reaction for selective labeling of proteins containing secondary amines. This method is employed for labeling mono-methyl lysine containing posttranslational modifications (PTMs) on proteins with various cargoes. The dysregulation of these mono methyl lysine PTMs has been linked to a variety of different biological malfunctions, yet the chemical methods for selective detection of mono methyl lysine PTMs are still lacking. This research provides a highly selective chemical tool that can effectively detect mono methyl lysine PTMs which, are present not only on histone proteins but also on other proteins and dictate various protein-protein interactions and functions. Thus, the proposed research has a great potential to further our understanding of how these PTMs regulate various cellular signaling processes and how the PTMs themselves are regulated.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.