Metal composition of marine cyanobacteria - an indicator of niche adaptation and cell physiological state?

海洋蓝藻的金属成分 - 生态位适应和细胞生理状态的指标？

• 批准号: NE/F003889/1
• 负责人: Mikhail Zubkov
• 金额: $ 4.79万
• 依托单位: NATIONAL OCEANOGRAPHY CENTRE
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2008
• 资助国家: 英国
• 起止时间: 2008 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FF003889%2F1
• 关键词: Metal; composition; marine; cyanobacteria; indicator

The oceans play a major role in determining the world's climate. In part this is due to the production of oxygen and the consumption of carbon dioxide by very small, single celled organisms, which are referred to as the photosynthetic picoplankton. Marine cyanobacteria of the closely-related genera Prochlorococcus and Synechococcus are the prokaryotic components of the photosynthetic picoplankton. Current and previous work in my lab has demonstrated that the in situ community structure of these organisms is fairly complex, with specific ecotypes or lineages occupying different niches to populate the world's oceans, allowing them to grow and photosynthesise under a broad range of environmental conditions. Whilst such molecular ecological studies can effectively map the spatial distributions of specific genotypes, the factors that dictate this global community structure are still poorly defined. This is important because changes in dominant picocyanobacterial lineages indicate major domain shifts in planktonic ecosystems and by observing and interpreting their distributions and physiological states we are essentially assessing changes in the rates of biogeochemical cycles. Athough the role of macronutrients, particularly N and P has received previous attention still there is a relative dearth of data on factors controlling picocyanobacterial community composition. Certainly, little if anything is known of the role of trace metals in this process. Thus, we hypothesise that in oceanic ecosystems genetically distinct picocyanobacteria are restricted to specific niches by their ability to acquire (limitation) or regulate trace metal accumulation (toxicity). In order to address this topic we propose to investigate trace metal (and macroelement) cell quotas in i) representatives of specific marine Prochlorococcus and Synechococcus lineages and to assess the affect of light stress and macronutrient shifts on these quotas and ii) in natural picophytoplankton assemblages using prior flow cytometric sorting, ICP-MS and X-ray microanalysis techniques. In so doing we will also obtain, for the first time, a real indication of picocyanobacterial cell physiological state over large spatial scales / in effect using elemental quotas as a proxy for what environment a given cell/population of cells is experiencing in situ / and hence can realistically begin to determine those macro and trace elements that are potentially depleted in situ and which are potentially restricting growth rate and/or yield.

海洋在确定世界气候方面起着重要作用。在一部分中，这是由于非常小的单细胞生物的氧气产生和二氧化碳消耗，这被称为光合作用的皮科普兰克顿。密切相关属氯环球菌和共氯环球菌的海洋蓝细菌是光合作用皮科普兰克顿的原始成分。我实验室中的当前和以前的工作表明，这些生物的原位社区结构相当复杂，特定的生态型或谱系占据了不同的壁ni以填充世界海洋，使它们可以在广泛的环境条件下生长和光合作用。尽管这种分子生态研究可以有效地绘制特定基因型的空间分布，但决定了这种全球社区结构的因素仍然很差。这很重要，因为主导性皮基分细菌谱系的变化表明浮游生物生态系统的主要领域转移，并且通过观察和解释其分布和生理状态，我们基本上正在评估生物地球化学周期速率的变化。 Athough大量营养素的作用，尤其是N和P的作用，但仍然受到了以前的关注，仍然相对缺乏控制皮基分细菌群落组成的因素。当然，几乎没有什么事在此过程中的痕量金属的作用。因此，我们假设在海洋生态系统中，遗传学上不同的皮基氨基杆菌仅限于特定的壁ni，因为它们的获取能力（限制）或调节痕量金属积累（毒性）。为了解决此主题，我们建议在i）使用先前的PicophyToplankton组装中使用先前流式的粒度分析米，ICP-MIC和X-RAY，在ICPophyToplankton组合中使用先前的流式细计学量，ICP-MICS和X-RAED，在ICP-MICS中，ICP-MICS和X-RAED，iCP-MICS和X-RAED，在ICP-MICS中，ICP-MIC和X-Ray areaire iCP-MIC和X-RAY iC-RAY和X-RAED，来研究特定的海洋前氯环球菌和Synechococcus谱系的痕量金属（和宏观元素）的配额，并评估对这些配额的光应力和大量偏移的影响。这样，我们还将首次获得巨大的空间尺度上的皮基摩裂细胞生理状态的真实指示 /使用元素配额作为代理给定的细胞 /细胞的环境的替代品，而在原位 /及其及其及其潜在地 /限制的范围或跟踪可能是局限性或屈服的情况下，这些细胞 /群体可能会开始存在，而这些宏和跟踪可能是局限性或限制的。