Collaborative Research: EAGER: Microfluidic assessment of chemotaxis towards different inorganic and organically complexed iron species by marine bacteria and phytoplankton

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。越来越多的证据表明，铁在调节世界海洋大片地区的大量浮游植物生产方面很重要，也影响浮游植物的物种形成。然而，并非海洋中的所有铁都是生物学上“可用的”，因此很难对这些联系进行定量了解。目前可用的方法依赖于向天然海水培养物中添加一种或另一种化学铁，但这种方法并不理想，因为它们无法控制培养物中铁的热化学或光化学循环。因此，需要新的分析方法来显示哪些形式的铁被不同的海洋细菌和浮游植物物种优先利用。加州大学圣克鲁兹分校的一名科学家与麻省理工学院的一名研究人员合作，计划确定一种新的微流体技术是否可以成功地用于研究海洋细菌和浮游植物中溶解有机物的利用，从而确定化学物种形成对这些物种获取铁的影响。具体来说，支持者计划证明微流体趋化性实验可以在微量金属清洁条件下进行，并表明海洋细菌和浮游植物对可识别的铁来源表现出趋化性。至于更广泛的影响，这项研究将为海洋科学界提供一种新技术，以记录不同的海洋细菌和浮游植物物种优先利用哪种形式的铁。麻省理工学院的一名博士后将作为EAGER奖励的一部分得到支持和培训。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).There is increasing evidence that iron is important in regulating bulk phytoplankton production in large regions of the world oceans and also influences the speciation of phytoplankton. However, not all iron in the ocean is biologically 'available', making it difficult to obtain a quantitative understanding of these linkages. Currently available methods that rely on adding one or another chemical species of iron to natural seawater cultures are not ideal because they cannot control for thermo- or photochemical cycling of iron species within the cultures. Thus, the need exists for new analytical methods to show which forms of iron are preferentially utilized by different marine bacteria and phytoplankton species. A scientist from the University of California, Santa Cruz in collaboration with a researcher from Massachusetts Institute of Technology plan to determine whether a new microfluidics technique successfully used to study dissolved organic matter utilization in marine bacteria and phytoplankton can be adapted to determine the effect of chemical speciation on iron acquisition by these species. Specifically, the proponents plan to demonstrate that the microfluidics chemotaxis experiments can be carried out under trace metal clean conditions and show that marine bacteria and phytoplankton display chemotaxis towards a recognizable source of iron. As regards broader impacts, this research would provide the ocean sciences community with a new technique to document which forms of iron are preferentially utilized by different marine bacteria and phytoplankton species. One postdoc from Massachusetts Institute of Technology would be supported and trained as part of this EAGER award.