CAREER: The Carbon Concentrating Mechanism of the Deep-sea Hydrothermal Vent Chemolithoautotroph Thiomicrospira Crunogena

事业：深海热液喷口化能自养生物 Thiomicrospira Crunogena 的碳浓缩机制

• 批准号: 0643713
• 负责人: Kathleen Scott
• 金额: $ 66.01万
• 依托单位: University of South Florida
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-03-01 至 2013-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0643713&HistoricalAwards=false
• 关键词: CAREER; Carbon; Concentrating; Mechanism; Deep

Chemolithoautotrophic bacteria obtain energy by oxidizing inorganic compounds such as sulfide, ammonia, and iron, and use this energy to power carbon dioxide and bicarbonate fixation. These organisms are of great ecological and environmental relevance; for example, they are the base of the food web at hydrothermal vents, occupy critical roles in the global nitrogen cycle, and acidify areas impacted by mine tailings. Some of their habitats have chronically or episodically low concentrations of carbon dioxide and bicarbonate, which puts organisms with an enhanced ability to grow under 'low carbon' conditions at a distinct advantage. It is reasonable to predict that many chemolithoautotrophs have extensive adaptations to cope with 'low carbon' conditions. The hydrothermal vent chemolithoautotroph Thiomicrospira crunogena has recently been demonstrated to act as a 'carbon dioxide vacuum'. It is capable of growing rapidly in the presence of vanishingly low concentrations of bicarbonate and carbon dioxide, and can somehow pack its cells with bicarbonate, to the point where the concentration of bicarbonate inside the cells is 100X higher than outside. Furthermore, T. crunogena's genome has recently been sequenced, which will greatly facilitate the discovery of the genes responsible for its 'carbon dioxide vacuuming' ability.The overall objective of this project is to physiologically and genetically characterize T. crunogena's ability to 'pump' vast quantities of bicarbonate and carbon dioxide into its cells. To meet this objective, both traditional physiological methods and cutting-edge molecular tools will be utilized. Chemolithoautotrophs catalyze processes of profound ecological and geochemical importance; developing an understanding of how they cope with an obvious environmental stressor will substantially enhance our capability to predict their activities in situ, and how they may be impacted by increasing concentrations of atmospheric carbon dioxide.Broader impactsThese research objectives rely heavily on genome data manually annotated by the undergraduate and graduate students enrolled in K. Scott's Genomics class. Spurred by the extraordinary enthusiasm of the students enrolled in this course, and by the growing importance of genome-level analyses in biological research, the principal investigator intends to expand genomics education to the secondary level. The objectives of the educational component are1. To create summer workshops in microbial genomics for secondary science educators. Five of the twenty educators enrolling per summer would be selected from schools with predominantly minority enrollment.2. To create a web-based interface allowing secondary students to interact with the PI and her graduate and undergraduate researchers to learn more about microbial genomics.3. To incorporate QRT-PCR into an upper-level Microbial Physiology Lab. This integrated approach to research and education will yield fundamental insights into chemolithoautotroph physiology, provide target genes for future analyses of environmental samples and key insights into the interpretation of genomic data from other microorganisms, and prepare secondary students to join the genomics revolution.

化能无机自养细菌通过氧化无机化合物如硫化物、氨和铁获得能量，并利用这种能量为二氧化碳和碳酸氢盐固定提供动力。 这些生物具有很大的生态和环境相关性;例如，它们是热液喷口食物网的基础，在全球氮循环中发挥关键作用，并使受尾矿影响的地区酸化。 它们的一些栖息地长期或偶尔具有低浓度的二氧化碳和碳酸氢盐，这使得生物体在“低碳”条件下生长的能力增强。可以合理地预测，许多化能无机自养生物具有广泛的适应性以科普“低碳”条件。 热液喷口化能自生生物Thiomicrospira crunogena最近被证明可以充当“二氧化碳真空”。 它能够在极低浓度的碳酸氢盐和二氧化碳存在下快速生长，并且可以以某种方式用碳酸氢盐包装其细胞，直到细胞内碳酸氢盐的浓度比外部高100倍。此外，T. crunogena的基因组最近已经测序，这将大大有助于发现负责其“二氧化碳真空”能力的基因。crunogena将大量碳酸氢盐和二氧化碳“泵”入细胞的能力。 为了实现这一目标，将利用传统的生理方法和尖端的分子工具。 化能无机自养生物催化具有深远生态学和地球化学意义的过程;了解它们如何科普明显的环境压力将大大提高我们预测它们原位活动的能力，以及它们如何受到大气二氧化碳浓度增加的影响。斯科特的基因组学课 由于参加这门课程的学生的非凡热情，以及基因组水平分析在生物研究中日益重要，首席研究员打算将基因组学教育扩大到中学水平。教育部分的目标是1.为中学科学教育工作者开设微生物基因组学暑期讲习班。 每年夏季入学的20名教育工作者中，有5名将从少数民族学生占多数的学校中挑选。创建一个基于网络的界面，让中学生与PI及其研究生和本科生研究人员进行互动，以了解更多关于微生物基因组学的知识。将QRT-PCR纳入上层微生物生理学实验室。这种研究和教育的综合方法将产生对化能自养生物生理学的基本见解，为环境样本的未来分析提供靶基因，并为解释其他微生物的基因组数据提供关键见解，并为中学生加入基因组学革命做好准备。