Contaminant stress on ecosystems: investigating microbial redox transformations of metal(loids) and novel tracers

生态系统的污染压力：研究金属（类物质）和新型示踪剂的微生物氧化还原转化

• 批准号: 327708-2011
• 负责人: Weisener, Christopher
• 金额: $ 1.6万
• 依托单位: University of Windsor
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=572111
• 关键词: Contaminant; stress; ecosystems; investigating; microbial

Interactions between minerals and microorganisms are of fundamental and growing interest due to their influence on the transport and toxicity of dissolved metal and metalloid ions in water-rock systems and their control on weathering and formation of minerals. The microbial processes that regulate the mass transport, transformations, and toxicity of metals in the environment are complex. Metals and metalloids can be enzymatically or non-enzymatically concentrated and dispersed by microbes in their environment. For example, studies in our lab have shown that metal/loids formed in the presence of bacteria can undergo dramatic transformation and speciation in changing redox environments. These differences of course, can depend on the bacterial species present, promoting template effects due to differences in cell wall structure between species. Even in single species, variations can result in metabolic state or the concentration and type of exudates (extracellular polymeric substance, EPS) produced during growth can affect the properties of the bio-minerals and thereby potentially influence their adsorptive capacity within the surrounding media. This research program will focus on key mineral systems (e.g. iron sulphate analogues such a jarosite end member minerals) influenced by reducing and oxidizing forms of bacteria. Experiments will use pure cultures and microbial consortia (isolated from iron reducing zones in sediments and soils). Natural iron sulphates including those formed in acid sulphate soil systems and synthesized end-members will be used in controlled laboratory experiments. In addition research within this program will also focus on developing new environmental tracers to characterize anthropogenic influences. Maintaining sustainable freshwater resources are directly tied to Canada's continued socio-economic success (i.e. agriculture, industry, people, and tourism). The minerals and energy industries in Canada are in the midst of their greatest expansion in the last three decades. This research program will enhance our understanding of how bacteria control metal release in natural ecosystems as well as those impacted by mining sector and anthropogenic inputs.

矿物质与微生物之间的相互作用是基本的，并且由于其对水摇滚系统中溶解金属和金属离子的运输和毒性的影响及其对矿物质的风化和形成的控制，因此具有越来越多的兴趣。调节环境中金属的质量传输，转化和毒性的微生物过程很复杂。金属和金属可以是酶或非酶浓缩的，并被微生物分散在其环境中。例如，我们实验室中的研究表明，在细菌存在下形成的金属/膜可以在变化的氧化还原环境中发生急剧转化和物种形成。当然，这些差异可以取决于存在的细菌物种，这是由于物种之间细胞壁结构的差异而促进模板效应。即使在单一物种中，变化也会导致代谢状态或生长过程中产生的渗出液的浓度和类型（细胞外聚合物，EPS）会影响生物 - 媒介的性质，从而可能影响其在周围介质中的吸附能力。该研究计划将着重于受到降低和氧化形式的细菌影响的关键矿物系统（例如硫酸铁类似物类似物）。实验将使用纯培养物和微生物联盟（从沉积物和土壤中的铁还原区域分离出来）。天然铁硫酸盐，包括在酸性硫酸盐土壤系统中形成的硫酸盐和合成的终端成员，将用于受控实验室实验。此外，该计划中的研究还将着重于开发新的环境示踪剂来表征人为影响。维持可持续的淡水资源与加拿大持续的社会经济成功（即农业，工业，人民和旅游业）直接相关。加拿大的矿产和能源行业正在过去三十年中最大的扩张。该研究计划将增强我们对细菌控制金属在天然生态系统中释放的理解，以及受矿业部门和人为输入影响的金属释放。