Collaborative Research: Antarctic Diatom Proteorhodopsins: Characterization and a Potential Role in the Iron-limitation Response

合作研究：南极硅藻蛋白视紫红质：特征及其在铁限制反应中的潜在作用

基本信息

批准号：
1745036
负责人：
Adrian Marchetti
金额：
$ 51.13万
依托单位：
University of North Carolina at Chapel Hill
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-06-01 至 2023-09-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1745036&HistoricalAwards=false
关键词：
Collaborative Research Antarctic Diatom Proteorhodopsins

项目摘要

Proteorhodopsins are proteins that are embedded in membranes that can act as light-driven proton pumps to generate energy for metabolism and growth. The discovery of proteorhodopsins in many diverse marine prokaryotic microbes has initiated extensive investigation into their distributions and functional roles. Recently, a proton-pumping, rhodopsin-like gene was identified in diatoms, a group of marine phytoplankton that dominates the base of the food web in much of the Southern Ocean. Since this time, proteorhodopsins have been identified in many, but not all, diatom species. The proteorhodopsin gene is more frequently found in diatoms residing in cold, iron-limited regions of the ocean, including the Southern Ocean, than in diatoms from other regions. It is thought that proteorhodopsin is especially suited for use energy production in the Southern Ocean since it uses no iron and its reaction rate is insensitive to temperature (unlike conventional photosynthesis). The overall objective of the project is to characterize Antarctic diatom-proteorhodopsin and determine its role in the adaptation of these diatoms to low iron concentrations and extremely low temperatures found in Antarctic waters. This research will provide new information on the genetic underpinnings that contribute to the success of diatoms in the Southern Ocean and how this unique molecule may play a pivotal role in providing energy to the base of the Antarctic food web. Broader impact activities are aimed to promote the teaching and learning of polar marine-sciences related topics by translating research objectives into readily accessible educational materials for middle-school students.This project will combine molecular, biochemical and physiological measurements to determine the role and importance of proteorhodopsin in diatom isolates from the Western Antarctic Peninsula region. Proton-pumping characteristics and pumping rates of proteorhodopsin as a function of light intensity and temperature, the resultant proteorhodopsin-linked intracellular ATP production rates, and the cellular localization of the protein will be determined. The project will examine the environmental conditions where Antarctic diatom-proteorhodopsin is most highly expressed and construct a cellular energy budget that includes diatom-proteorhodopsin when grown under these different environmental conditions. Estimates of the energy flux generated by proteorhodopsin will be compared to total energy generation by the photosynthetic light reactions and metabolically coupled respiration rates. Finally, the characteristics and gene expression of diatom-proteorhodopsin in Antarctic diatoms and a proteorhodopsin-containing diatom isolates from temperate regions will be compared in order to determine if there is a preferential dependence on energy production through proteorhodopsin in diatoms residing in cold, iron-limited regions of the ocean. Educational activities will be performed in collaboration with the Morehead Planetarium and Science Center who co-ordinates the SciVentures program, a popular summer camp for middle-school students from Chapel Hill and surrounding areas. In collaboration with the Planetarium, the researchers will develop activities that focus on phytoplankton and the important role they play within polar marine food webs for the SciVentures participants. Additionally, a teaching module on Antarctic phytoplankton will be developed for classrooms and made available to educational networking websites and presented at workshops for science educators nationwide.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.

蛋白质蛋白是蛋白质的蛋白质，它们嵌入在膜中，可以充当照明质子泵，以产生代谢和生长的能量。在许多多样化的海洋原核微生物中发现蛋白质的蛋白酶已开始对其分布和功能作用进行广泛研究。最近，在硅藻的一群海洋浮游植物中鉴定出了一种质子泵，类似Rhodopsin的基因，该基因在南大部分地区的大部分地区占据了食物网的基础。从那时起，已经在许多但不是全部的硅藻物种中鉴定出蛋白质蛋白。蛋白质淡季基因在居住在包括南大洋在内的寒冷的铁限制区域的硅藻中，而不是其他地区的硅藻。人们认为，蛋白质淡淡的蛋白质特别适合在南大洋中使用能源生产，因为它不使用铁，并且其反应速率对温度不敏感（与常规光合作用不同）。该项目的总体目的是表征南极硅藻汀类动物蛋白，并确定其在这些硅藻适应低铁浓度和在南极水中发现极低温度的作用。这项研究将提供有关遗传基础的新信息，这些基础有助于在南洋中硅藻的成功，以及该独特的分子在为南极食品网的基础提供能量方面如何发挥关键作用。更广泛的影响活动旨在通过将研究目标转化为中学学生的易于访问的教育材料来促进与北极海洋学相关的主题的教学和学习。该项目将结合分子，生物化学和生理测量，以确定蛋白质蛋白在diatom蛋白中的作用和重要性。蛋白质淡淡蛋白质蛋白的质子泵化特性和泵送速率是光强度和温度的函数，所得的蛋白淡季蛋白蛋白连接的细胞内ATP产生速率以及蛋白质的细胞定位。该项目将检查南极硅藻甲摩丁素的环境条件，并构建一个细胞能量预算，其中包括在这些不同的环境条件下生长的硅藻 - 甲状腺素。通过光合光反应和代谢耦合呼吸速率将蛋白淡淡蛋白酶产生的能量通量的估计值与总能量产生进行比较。最后，将比较来自温带区域的硅藻硅藻中硅藻 - 甲状腺素的特征和基因表达和含有蛋白淡淡蛋白质的硅二他的分离株在温带区域中分离株，以确定在居住在冷，铁层的海洋中的硅藻中，通过蛋白质的蛋白质蛋白质的优先依赖性依赖能量依赖性。教育活动将与莫尔黑德天文馆和科学中心合作进行，后者协调Sciventures计划，这是一个受欢迎的夏令营，适合来自教堂山及周边地区的中学学生。研究人员将与天文馆合作，开展关注浮游植物的活动，以及他们在Sciventures参与者的Polar Marine Food Web中发挥的重要作用。此外，将为课堂上开发有关南极浮游植物的教学模块，并在全国科学教育工作者的研讨会上提供给教育网站，并在全国范围内为教育网站提供。该奖项反映了NSF的法定任务，并认为通过基金会的知识和更广泛的影响，通过评估来获得支持，并被认为是值得的支持。

项目成果

期刊论文数量（6）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Low diversity of a key phytoplankton group along the West Antarctic Peninsula

DOI：
10.1002/lno.11765
发表时间：
2021-05-06
期刊：
LIMNOLOGY AND OCEANOGRAPHY
影响因子：
4.5
作者：
Brown, Michael S.;Bowman, Jeff S.;Schofield, Oscar M.
通讯作者：
Schofield, Oscar M.

Interactive effects of iron and light limitation on the molecular physiology of the Southern Ocean diatom Fragilariopsis kerguelensis

铁和光限制对南大洋硅藻 Fragilariopsisäkerguelensis 分子生理学的相互作用影响

DOI：
10.1002/lno.11404
发表时间：
2020
期刊：
Limnology and Oceanography
影响因子：
4.5
作者：
Moreno, Carly M.;Gong, Weida;Cohen, Natalie R.;DeLong, Kimberly;Marchetti, Adrian
通讯作者：
Marchetti, Adrian