Gaining insights into the physiology of neutrophilic, iron-oxidizing chemolithoautotrophs.

该行动资助 2015 财年 NSF 生物学博士后研究奖学金，扩大参与范围。该奖学金支持研究员所在实验室的研究和培训计划，以及扩大科学领域代表性不足群体参与的计划。 Roman A. Barco 博士的这项研究计划的标题是“深入了解自养、铁氧化微生物的生理学”。该奖学金的主办机构是毕格罗海洋科学实验室 (BLOS) 和南加州大学 (USC)。资助科学家是 David Emerson 博士（BLOS 的主要资助者）和 Kenneth Nealson 博士（南加州大学的共同资助者）。变形菌门由大量不同的细菌组成，包括许多病原体，但也有许多对人类有益的细菌，例如对农业至关重要的固氮细菌。变形菌门中的一类 Zetaproteobacteria 在全球铁循环中发挥着关键作用。迄今为止，所有已分离出的 Zetaproteobacteria 都通过氧化铁来获取能量。它们在氧气浓度低且 pH 值介于酸性和碱性之间（称为中性 pH 值 6 至 8）的海洋环境中数量丰富且非常活跃。除了氧化铁之外，它们还固定碳，使它们成为与高铁含量相关的海洋生境中的初级生产者（自养生物），例如热液喷口、洋壳和深海地下。然而，尽管有这些重要的环境作用，但它们的生理学尚未阐明，需要进一步研究。方便地，已经分离出 Zetaproteobacteria 的近亲，其生长不需要铁，并且与野生型相比，可以鉴定进行铁氧化的蛋白质。一群来自伽马变形菌纲的细菌硫微螺菌通过氧化硫来获取能量。它的基因组已被测序，使得在最基本的水平上比较铁和硫氧化剂的生理学成为可能。在该研究期间进行的此类分析有望对变形菌门不同类别的铁氧化机制提供有用的见解。这两种类型的细菌都可能在许多生物技术应用中有用，包括生物修复。该奖学金的培训目标包括获得生物信息学的编程技能，特别是分析下一代测序数据和学习电微生物学技术、使用电极来富集和分离微生物。该研究员充当两个主办机构本科生的榜样和导师，并通过社区大学联系 (CCC) 计划与暗能量生物圈调查中心合作。 CCC 项目针对加利福尼亚州洛杉矶及周边地区的社区大学，传播有关环境微生物学及其与地质学、化学和海洋学等其他科学领域的联系的信息。

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2015, Broadening Participation. The fellowship supports a research and training plan in a host laboratory for the Fellow and a plan to broaden participation of groups under-represented in science. The title of the research plan for this fellowship to Dr. Roman A. Barco is "Gaining insights into the physiology of autotrophic, iron-oxidizing microorganisms." The host institutions for this fellowship are Bigelow Laboratory for Ocean Sciences (BLOS) and the University of Southern California (USC). The sponsoring scientists are Dr. David Emerson (lead sponsor at BLOS) and Dr. Kenneth Nealson (co-sponsor at USC).The phylum Proteobacteria comprises a large and varied group of bacteria, including many pathogens but also many of benefit to humans, e.g., nitrogen-fixing bacteria crucial to agriculture. A class within the Proteobacteria phylum, the Zetaproteobacteria, plays a key role in the global iron cycle. All the Zetaproteobacteria that have been isolated to date obtain energy by oxidizing iron. They are both abundant and very active in marine environments with low concentrations of oxygen and with conditions that fall between acid and basic pH, known as circumneutral pH (pH 6 to 8). In addition to oxidizing iron, they also fix carbon, making them primary producers (autotrophs) in marine habitats associated with high iron content, such as hydrothermal vents, the oceanic crust and the deep marine subsurface. Yet despite these important environmental roles, their physiology has not been elucidated and requires further study. Conveniently, a Zetaproteobacteria relative has been isolated that does not require iron for its growth and, by comparison with the wild type, allows for identification of the proteins that carry out iron oxidation. A group of bacteria from the Gammaproteobacteria class, Thiomicrospira, obtains energy by oxidizing sulfur. Its genome has been sequenced, making it possible to compare the physiology of iron and sulfur oxidizers at the most basic level. Such analysis conducted during this fellowship promises useful insights into the mechanisms of iron-oxidation across different classes of the Proteobacteria phylum. Both of these types of bacteria are potentially useful in a number of biotechnology applications, including bioremediation. Training goals for the fellowship include acquiring programming skills for bioinformatics, especially for analyzing next-generation sequencing data and learning techniques in electromicrobiology, the use of electrodes to enrich and isolate microorganisms. The Fellow serves as a role model and mentor to undergraduate students at both host institutions and collaborates with the Center for Dark Energy Biosphere Investigations via the Community College Connections (CCC) program. The CCC program targets community colleges in Los Angeles, CA and surrounding areas, to disseminate information about environmental microbiology and how it links to other scientific fields such as geology, chemistry, and oceanography.