MCA: Characterizing the role of alternative oxidases in marine bacteria

细菌在我们的星球上非常丰富，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，如养分循环。它们有惊人的多种途径来产生生存和运作所需的能量，这些途径是它们生存和促进生态系统进程的能力的基础。尽管这一点很重要，但对于特定能量产生途径的功能如何与细菌适应性以及这些生物体在我们环境功能中的作用，我们仍然缺乏了解。该项目的重点是更好地了解替代氧化酶（AOX）如何在海洋细菌的生长和生存中发挥作用，AOX是海洋细菌能量生成途径的一个组成部分，在营养循环中起着至关重要的作用。该奖项将使研究人员能够发展他们将用于发现替代氧化酶在不同细菌中的表达和功能的技能，并开始将其与营养循环途径联系起来。此外，研究者将把这些研究活动与学生培训结合起来，拓展到夏威夷和大陆的K-12学生，并在他们的家乡机构发展新的多样性，公平和包容的努力。近年来，对真核生物中AOX功能的研究是一个非常活跃的领域。对植物、原生生物、真菌和动物的研究揭示了AOX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作用。然而，在研究者对费氏弧菌的研究之外，AOX在海洋细菌中的生理作用基本上是未知的。尚未解决的问题包括AOX如何在不同的细菌中发挥作用，编码AOX的细菌的生理途径是否存在共性，环境条件与编码AOX的细菌的存在之间是否存在相关性。该项目将通过三种方法来解决这些知识空白：1)微呼吸法以及遗传、生化和分子方法来确定菲氏弧菌AOX在环境相关条件下的生理作用；2)通过遗传学、分子生物学和生物化学的方法来了解AOX在其他不同海洋模式细菌中的调控和生理贡献；3)利用生物信息学方法识别与aox丰度和表达相关的基因组特征和环境条件。本研究结果将为进一步了解AOX在细菌中的调控和功能提供有价值的新信息，为进一步探索细菌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。这些结果也将为了解不同生物王国中AOX的调节和功能的共性提供见解。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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.