Research Starter Grant: Characterization of Genetic and Biochemical Mechanisms of Iron Acquisition by Pseudomonas mendocina strain ymp

铁是地球上最丰富的元素，因此，大多数生命形式都进化出对铁的必然依赖也就不足为奇了。然而，在好氧条件下，大部分铁以不溶性铁矿物的形式存在。为了应对这样的环境压力，原核生物进化出了一些策略，例如使用铁载体从有限的可溶性供应中隔离铁。铁载体和产生铁载体的微生物确实已被证明对矿物溶解速度有重大影响。假单胞菌Mendocina菌株YMP对铁载体的产生和矿物的溶解已有研究，但对任何菌株的遗传含量知之甚少。这项研究的目标是通过铁载体介导的途径和意外的铁吸收途径来表征参与铁吸收的基因。对这些途径的描述将有助于更好地理解微生物如何在生物地球化学过程中发挥重要作用，并有可能为加强生物修复提供独特的解决方案。该项目将通过将夏威夷少数族裔本科生和研究生的课堂教育和实验室培训结合起来，促进环境分子微生物学领域的学生培训。夏威夷大学希洛分校致力于本科教育，是一所为少数族裔服务的机构。大约68%的学生是夏威夷居民，其中21%是夏威夷原住民。该项目将包括以下教育部分：1)在使用分子、生化和微生物学技术的多学科实验室中为本科生和研究生提供实践培训；2)指导和引入少数族裔本科生作为暑期研究实习生到实验室从事环境分子微生物学项目；3)开发一门以实验室为基础的课程，将课堂讨论/讲座和高年级本科生的实践经验结合在一起。

Iron is the most abundant element on earth and thus it is not surprising that most forms of life have evolved an obligate dependence on iron. However, under aerobic conditions the majority of iron exists as insoluble ferric mineral forms. In response to such environmental pressures, prokaryotes have evolved strategies such as the use of siderophores for sequestering iron from a limited soluble supply. Siderophores and siderophore-producing microbes have indeed been shown to have significant effects on rates of mineral dissolution. Pseudomonas mendocina strain ymp has been studied for siderophore production and mineral dissolution, but very little is known about the genetic content of any strain of P. mendocina. The goals of this research project are to characterize genes involved in iron uptake by both siderophore-mediated pathways, and by unanticipated iron uptake pathways. The characterization of such pathways in P. mendocina will lead to a greater understanding of how microorganisms play an important role in biogeochemical processes as well as potentially providing unique solutions to enhance bioremediation. Broader Impacts This project will facilitate student training in the field of environmental molecular microbiology by integrating classroom education and laboratory training for minority undergraduates and graduate students of Hawaii. The University of Hawaii at Hilo is dedicated to undergraduate education and is a minority-serving institution. Approximately 68% of students are residents of Hawaii and 21% of those students are Native Hawaiian. The project will have the following educational components: 1) providing hands-on training of undergraduate and graduate students in a multidisciplinary laboratory using molecular, biochemical, and microbiological techniques; 2) mentoring and bringing in minority undergraduates to the laboratory to work on environmental molecular microbiology projects as summer research interns; 3) developing a laboratory-based course in environmental microbiology, which integrates classroom discussions/lectures and hands-on experience for senior undergraduates.