Deciphering the structure and chemistry of microbial mat-fluid-mineral interactions in three-dimensions for application to environmental challenges

微生物可以忍受极端的温度、酸度和高浓度的溶解金属。这些生物通常以微生物席的形式生长，这些微生物席是在表面流体边界发现的层状结构。微生物垫寄主微生物表现出各种代谢途径，其中一些可以沉淀或溶解经济或环境重要的矿物质。这种促进地球化学反应的能力意味着微生物垫可以被认为是自然发生的生物反应器，在地球生命的整个历史中影响着环境。提出的研究旨在开发一个地质微生物“工具箱”，用于表征和修复策略，以应用于自然环境和工业场景。这将通过三个目标来实现：1)在三维空间中解决微生物垫结构和化学问题，2)暂时限制微生物生物矿化过程，以及3)将生物矿化应用于环境挑战。从不列颠哥伦比亚省卡里布高原地区的湖泊中收集的蓝藻占主导地位的草席和微生物将是主要的目标标本。这些地点是加拿大现代叠层石形成和宿主微生物群落的最佳范例之一，适合拟议的碳酸化和金属反应性实验。这项研究将提高我们观察微生物席结构和化学的能力，这一结果将对整个地球微生物学领域产生影响。这些进展将有助于表征与流体化学和微生物活动有关的微生物碳酸盐矿物成核反应。叠层石微化石中保存的有机物的结构和光谱分析将产生一个当代碳酸盐矿物相生物特征保存的例子。微生物结合金属的能力将在金属暴露实验中进行研究。金属暴露后，外聚合物生产和蓝藻光合活性的变化将揭示这些生物在固定溶液时如何耐受金属。这些结果将与碳酸盐沉淀实验结果相结合，通过测试金属在生物碳酸盐矿物中的固定化潜力。目的是开发一种生物地球化学过程，通过这种过程，有毒金属和大气中的碳可以在良性碳酸盐相中共同隔离。开发用于矿山尾矿储存设施的配对碳封存和金属修复将有助于加拿大各地的矿山现场修复，这是本研究计划的长期目标。该项目将通过高素质学生的努力取得成功，他们将获得分析技术、实验设计、批判性思维和沟通方面的经验。学生将在他们选择的学术、工业和政府部门的就业途径中成为资产。

Microbes can endure extremes in temperature, acidity, and high concentrations of dissolved metals. These organisms often grow as microbial mats, which are layered structures found at surface-fluid boundaries. Microbial mats host microbes exhibiting various metabolic pathways, some of which can precipitate or dissolve economically or environmentally important minerals. This capacity to facilitate geochemical reactions means that microbial mats can be thought of as naturally occurring bioreactors that have impacted the environment throughout the history of life on Earth. The proposed research aims to develop a geomicrobiological `toolbox' of characterization and remediation strategies for application to natural environments and industrial scenarios. This will be targeted through three objectives: 1) resolving microbial mat structure and chemistry in three-dimensions, 2) temporally constraining microbial biomineralization processes, and 3) applying biomineralization to environmental challenges. Cyanobacteria dominated mats and microbialites collected from lakes in the Cariboo Plateau region in British Columbia will be the primary target specimens. These sites are among the best examples of modern stromatolite formation in Canada and host microbial communities suitable for the proposed carbonation and metal reactivity experiments. The proposed research will improve our ability to observe microbial mat structure and chemistry, a result that will have impact across the field of Geomicrobiology. These developments will aid characterization of microbial carbonate mineral nucleation reactions studied in relation to fluid chemistry and microbial activity. Structural and spectral analyses of organic matter preserved in stromatolite microfossils will yield a contemporary example of biosignature preservation in carbonate mineral phases. The ability of microbes to bind metals will be studied in metal exposure experiments. Changes in exopolymer production and cyanobacteria photosynthetic activity in response to metal exposure will reveal how these organisms tolerate metals while immobilizing them from solution. These outcomes will be combined with the carbonate precipitation experiment results by testing the potential for metals to be immobilized in biogenic carbonate minerals. The aim is to develop a biogeochemical process by which toxic metals and atmospheric carbon can be co-sequestered in benign carbonate phases. Developing paired carbon sequestration and metal remediation for deployment at mine tailing storage facilities will aid mine site remediation across Canada and is a long term goal of this research program. The program will succeed through the efforts of highly qualified students who will gain experience in analytical techniques, experiment design, critical thinking, and communication. Students will become assets in the employment avenues they chose to pursue across academic, industrial, and government sectors.