MCA: Characterizing the role of alternative oxidases in marine bacteria

细菌在我们的星球上大量存在，在不同的环境中定居，并在重要的生态系统过程中发挥重要作用，如营养循环。它们有各种各样的途径来产生它们生活和运作所需的能量，这些途径是它们生存和为生态系统进程做出贡献的能力的基础。尽管这很重要，但对于特定能量生成途径的功能如何与细菌的适应性以及这些微生物在环境功能中的作用之间的联系，我们缺乏了解。该项目的重点是更好地了解替代氧化酶(AOX)--海洋细菌能量产生途径的一个组成部分，在营养循环中发挥关键作用--如何在它们的生长和生存中发挥作用。这一奖项将允许研究人员开发他们将使用的技能，以发现替代氧化酶如何在不同的细菌中表达和发挥作用，并开始将其与营养循环途径联系起来。此外，研究人员将把这些研究活动与学生培训、对夏威夷和大陆的K-12学生的外展，以及在本国机构发展新的多样性、公平性和包容性的努力结合起来。近年来，真核生物中AOX功能的研究一直非常活跃。对植物、原生动物、真菌和动物的研究揭示了AOX活性在帮助细胞有效应对环境压力和维持能量平衡方面的共同线索。然而，除了研究人员对费氏弧菌的研究外，AOX在海洋细菌中的生理作用(S)基本上还没有被探索。尚未回答的问题包括AOX如何在不同的细菌中发挥作用，AOX编码细菌的生理途径是否有共同点，或者环境条件与AOX编码细菌的存在之间是否存在相关性。该项目将使用三种方法解决这些知识空白：1)微呼吸测量以及遗传、生物化学和分子方法，以确定AOX在环境相关条件下的生理作用；2)遗传、分子和生化方法，以了解AOX在其他不同模式海洋细菌中的调节和生理贡献(S)；以及3)生物信息学方法，以确定与AOX丰度和表达相关的基因组特征和环境条件。本研究结果将为细菌AOX的调控和功能提供有价值的新信息，为进一步探讨细菌AOX对微生物生理、海洋生态系统功能和生物地球化学循环的影响奠定基础。这些结果还将提供对AOX在不同生活王国的监管和功能方面的共性的洞察。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Bacteria are abundant on our planet, colonizing diverse environments and playing essential roles in important ecosystem processes such as nutrient cycling. They have an amazing diversity of pathways for generating the energy they need to live and function, and these pathways underlie their survival and ability to contribute to ecosystem processes. Despite this importance, there is a lack of knowledge of how the function of specific energy generation pathways connects to bacterial fitness and these organisms’ role in the function of our environment. This project focuses on better understanding how alternative oxidase (AOX), a component of energy-generating pathways of marine bacteria that play vital roles in nutrient cycling, functions in their growth and survival. This award will allow the investigator to develop skills they will use to discover how alternative oxidase is expressed and functions in diverse bacteria and begin to connect this to nutrient cycling pathways. In addition, the investigator will couple these research activities with student training, outreach to K-12 students in Hawaii and the mainland, and the development of new diversity, equity, and inclusion efforts at their home institution.Research on AOX function in eukaryotes has been a very active area in recent years. Studies in plants, protists, fungi, and animals have revealed a common thread in AOX activity in helping cells deal effectively with environmental stresses and maintain energy balance. However, outside of the investigator’s work in Vibrio fischeri, the physiological role(s) of AOX in marine bacteria is essentially unexplored. Unanswered questions include how AOX functions in diverse bacteria and whether there are commonalities in physiological pathways in AOX-encoding bacteria or correlations between environmental conditions and the presence of aox-encoding bacteria. This project will address these knowledge gaps using three approaches: 1) microrespirometry along with genetic, biochemical, and molecular approaches to determine the physiological role of V. fischeri AOX under environmentally relevant conditions; 2) genetic, molecular, and biochemical approaches to understand the regulation and physiological contribution(s) of AOX in other diverse model marine bacteria; and 3) bioinformatic approaches to identify the genomic features and environmental conditions that correlate with aox abundance and expression. The results of this research will provide valuable new information about AOX regulation and function in bacteria and lay the foundation for further exploration of the influence of bacterial AOX on microbial physiology, marine ecosystem function, and biogeochemical cycling. These results will also provide insight into commonalities in the regulation and function of AOX in different kingdoms of life.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.