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.

化学部的生命过程化学项目正在资助佐治亚州立大学的 Samer Gozem 博士，研究地球表面受到大部分光激发后光氧电压 (LOV) 蛋白质域中发生的分子和电子事件。依赖太阳能的生物体（例如藻类和植物）必须感知并响应不断变化的光照条件，LOV 域是一类利用黄素分子吸收的蛋白质。 Gozem 博士将结合经典和量子力学计算机模拟来研究蛋白质中的特定氨基酸在光吸收时如何协调 LOV 域中黄素的电子结构的变化。这项研究建立的模型对基于 LOV 的可编码生物传感器、灯开关和活性氧发生器的设计具有潜在的长期影响，该项目预计将开发更容易使用的自动化和用户友好的计算化学工具。到非计算学生和科学家，包括来自代表性不足的少数群体的学生，将在研究沉浸活动中使用这些计算工具来了解多学科科学和研究。佐治亚州立大学将一门将量子力学与化学和生物学联系起来的跨学科课程引入到课程中。LOV 光感受器与普遍存在的生物辅因子黄素结合，但与其他黄素蛋白光感受器经历不同的光化学反应。在激发下，LOV黄素经历系间穿越到三重态，与附近保守的半胱氨酸残基形成加合物，诱导变构反应，然后通过热或在某些情况下通过光化学恢复到暗状态。该机制的机制在不同的生物体中或在诱变时有所不同，该项目将研究来自三个生命界（植物、细菌和细菌）的典型 LOV 域中 LOV 光循环每个步骤的机制细节。真菌）并试图阐明 LOV 结构域蛋白序列变化如何改变黄素辅因子的光物理和光化学性质。本研究中开发和使用的计算方法包括静电调谐图和混合量子力学/分子力学 (QM/MM) 工具。 QM/MM 计算是使用 MM 子系统进行的，该子系统部分捕获分子动力学模拟生成的蛋白质结构整体，以采样局部侧链灵活性。该奖项反映了 NSF 的法定使命，并被认为值得支持通过使用基金会的智力优点和更广泛的影响审查标准进行评估。

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