CAREER: Shedding light on the Photochemistry of the LOV Class of Flavin Photoreceptors

职业：揭示 LOV 类黄素光感受器的光化学

基本信息

批准号：
2047667
负责人：
Samer Gozem
金额：
$ 69.84万
依托单位：
Georgia State University Research Foundation, Inc.
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2021
资助国家：
美国
起止时间：
2021-08-01 至 2026-07-31
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2047667&HistoricalAwards=false
关键词：
CAREER Shedding light Photochemistry LOV

项目摘要

The Chemistry of Life Processes Program in the Chemistry Division is funding Dr. Samer Gozem from Georgia State University to investigate the molecular and electronic events that occur in Light-Oxygen-Voltage (LOV) protein domains following light excitation. The earth’s surface receives the majority of its energy from solar radiation. Organisms that depend on solar energy, such as algae and plants, must sense and respond to changing light conditions. LOV domains are a class of proteins that use the molecule flavin to absorb light and help organisms sense their environments. Dr. Gozem will apply a combination of classical and quantum mechanical computer simulations to study how specific amino acids in the protein coordinate changes in the electronic structure of the flavin in LOV domains upon light absorption. The fundamental principles to be established by this study have potential long term impact for the design of LOV-based encodable biosensors, light switches, and generators of reactive oxygen species. The project is anticipated to develop automated and user-friendly computational chemistry tools that are more readily accessible to non-computational students and scientists. High school and undergraduate students, including those from under-represented minority groups, are to be introduced to multidisciplinary science and research using these computational tools in research immersion activities. An additional educational goal is to assess the impact of introducing an interdisciplinary course connecting quantum mechanics to chemistry and biology into the curriculum at Georgia State University.LOV photoreceptors bind the ubiquitous biological cofactor flavin, but undergo distinct photochemistry from other flavoprotein photoreceptors. Upon excitation, the LOV flavin undergoes intersystem crossing to a triplet state, forms an adduct with a nearby conserved cysteine residue, induces an allosteric response, and then reverts to the dark state thermally or, in some cases, photochemically. However, the details of this mechanism vary in different organisms or upon mutagenesis. This project will investigate the mechanistic details of each step of the LOV photocycle in prototypical LOV domains from three kingdoms of life (plants, bacteria, and fungi) and seeks to elucidate how LOV domain protein sequence variations alter the photophysical and photochemical properties of the flavin cofactor. The computational methods being developed and employed in this research include electrostatic tuning maps and hybrid quantum mechanical/molecular mechanical (QM/MM) tools. The QM/MM calculations are being performed with an MM subsystem that partially captures the protein structural ensemble generated by molecular dynamics simulations to sample local side chain flexibility.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.

化学司的化学过程计划是为佐治亚州立大学的Samer Gozem博士提供资金，以研究光兴奋后的光氧 - 电压（LOV）蛋白质结构域中发生的分子和电子事件。地球表面从太阳辐射中获得大部分能量。取决于太阳能的生物，例如藻类和植物，必须感知并应对变化的光条件。 LOV域是一类使用分子黄素吸收光并帮助生物感知其环境的蛋白质。 Gozem博士将使用经典和量子机械计算机模拟的组合来研究蛋白质坐标中黄素电子结构在LOV域中的电子结构中的特定氨基酸在光吸收中如何变化。这项研究要确定的基本原理对基于LOV的编码生物传感器，光开关和活性氧的发电机的设计具有潜在的长期影响。预计该项目将开发自动化和用户友好的计算化学工具，这些工具对非竞争学生和科学家更容易访问。高中和本科生，包括来自代表性不足的少数群体的学生，将在研究沉浸式活动中使用这些计算工具介绍多学科科学和研究。另一个教育目标是评估引入跨学科课程，将量子力学与化学和生物学连接到佐治亚州立大学的课程中。LOV光感受器结合了无处不在的生物辅助剂黄素，但经历了其他黄素蛋白光感受器的独特光化学。兴奋后，LOV黄素经历了三胞胎的间交叉，形成与附近保守的半胱氨酸住宅的加合物，引起变构反应，然后在某些情况下以光化的方式恢复到黑暗状态。但是，这种机制的细节在不同的生物体或诱变中有所不同。该项目将研究来自生命三个王国（植物，细菌和真菌）的原型LOV领域中LOV光循环的每个步骤的机械细节，并试图阐明LOV结构域蛋白序列的变化如何改变黄素辅助器的光学和光化学特性。本研究中开发和使用的计算方法包括静电调整图和杂交量子机械/分子机械（QM/mm）工具。 QM/MM计算是通过MM子系统进行的，该系统部分捕获了由分子动力学模拟产生的蛋白质结构集合，以样品采样局部侧链灵活性。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子和更广泛影响的评估来审查审查的审查标准来通过评估来获得的支持。

项目成果

期刊论文数量（9）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Ionic Atmosphere Effect on the Absorption Spectrum of a Flavoprotein: A Reminder to Consider Solution Ions

DOI：
10.1021/acs.jpclett.1c02173
发表时间：
2021-08-26
期刊：
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
影响因子：
5.7
作者：
Dratch, Benjamin D.;Orozco-Gonzalez, Yoelvis;Gozem, Samer
通讯作者：
Gozem, Samer

OS100: A Benchmark Set of 100 Digitized UV–Visible Spectra and Derived Experimental Oscillator Strengths

OS100：100 个数字化紫外可见光谱和衍生实验振荡器强度的基准集

DOI：
10.1021/acs.jpca.1c08988
发表时间：
2022
期刊：
The Journal of Physical Chemistry A
影响因子：
0
作者：
Tarleton, Astrid S.;Garcia-Alvarez, Jorge C.;Wynn, Anah;Awbrey, Cade M.;Roberts, Tomas P.;Gozem, Samer
通讯作者：
Gozem, Samer

The effect of hydrogen-bonding on flavin’s infrared absorption spectrum

氢键对黄素红外吸收光谱的影响

DOI：
10.1016/j.saa.2021.120110
发表时间：
2021
期刊：
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
影响因子：
0
作者：
Kabir, Mohammad Pabel;Orozco-Gonzalez, Yoelvis;Hastings, Gary;Gozem, Samer
通讯作者：
Gozem, Samer

Photochemically triggered cheletropic formation of cyclopropenone (c-C 3 H 2 O) from carbon monoxide and electronically excited acetylene

光化学触发一氧化碳和电子激发乙炔形成环丙烯酮 (c-C 3 H 2 O)

DOI：
10.1039/d2cp01978g
发表时间：
2022
期刊：
Physical Chemistry Chemical Physics
影响因子：
3.3
作者：
Wang, Jia;Kleimeier, N. Fabian;Johnson, Rebecca N.;Gozem, Samer;Abplanalp, Matthew J.;Turner, Andrew M.;Marks, Joshua H.;Kaiser, Ralf I.
通讯作者：
Kaiser, Ralf I.

Photoelectron Spectroscopy of Oppositely Charged Molecular Switches in the Aqueous Phase: Theory and Experiment