SGER: The Response of Marine Phytoplankton to Climate Change: Characterization of Rubisco Activase

SGER：海洋浮游植物对气候变化的响应：Rubisco 激活酶的表征

• 批准号: 0224078
• 负责人: Rose Ann Cattolico
• 金额: $ 6.49万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2004-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0224078&HistoricalAwards=false
• 关键词: SGER; Response; Marine; Phytoplankton; Climate

Inorganic carbon plays a crucial role in regulating marine productivity and species composition in phytoplankton communities. Therefore understanding the mechanisms underlying inorganic carbon fixation by different phytoplankton assemblages is critical if we are to understand the response of phytoplankt on photosynthesis to global climate change, and to develop realistic models of biogeochernical carbon flux in the ocean.Rubisco is a keystone enzyme that drives Calvin cycle function. However, it is now well documented that terrestrial plant Rubisco is catalytically non?functional without the co?operative interplay of Rubisco activase. To date, no information exists in the literature concerning the function of Rubisco activase for gLny chromophytic alga. In fact, except for Heterosigma akashiwo and two Cylindrotheca species, no data exists on Rubisco catalytic function for any other representative of this assemblage that is so critical in global carbon processing.The Goals of this project are to: a) Isolate and characterize Rubisco activase using Heterosigma as model chromophytic algal species; and, in particular, to b) Extend Rubisco activase studies to include diatoms since they rank as primary contributors in C02 management.The study is feasible because: a) The cloned, putative Heterosigma activase gene has now been over?expressed in E. coli; b) Extensive analysis of Heterosigma Rubisco has been accomplished; c) Patterns of Rubisco mRNA production in response to light cues have been documented; d) Heterosigma and diatom Rubisco antibodies have been shown to cross react; e) Flow cytometric measurements of antibody?tagged Rubisco have been made.While the effort in understanding the regulation of Rubisco by Rubisco activase in phytoplankton may be risky, this study will establish a primary database for chromophytic algae wherein the biochemistry of inorganic carbon processing via Rubisco/Rubisco activase interaction is deciphered. The long?term benefit this study is highly significant when considered in terms of predicting photosynthetic performance in response to climate change.

无机碳在调节海洋生产力和浮游植物群落物种组成方面发挥着至关重要的作用。因此，如果我们要了解浮游植物光合作用对全球气候变化的响应，并开发海洋生物地球化学碳通量的现实模型，了解不同浮游植物组合的无机碳固定机制至关重要。Rubisco 是驱动卡尔文循环功能的关键酶。然而，现在有充分证据表明，如果没有 Rubisco 激活酶的协同相互作用，陆地植物 Rubisco 将无法发挥催化作用。迄今为止，文献中尚无关于 Rubisco 激活酶对 gLny 有色藻的功能的信息。事实上，除了 Heterosigma akashiwo 和两个 Cylindrotheca 物种外，没有关于该组合的任何其他代表的 Rubisco 催化功能的数据，该组合在全球碳处理中至关重要。该项目的目标是： a) 使用 Heterosigma 作为有色藻模型物种来分离和表征 Rubisco 激活酶； 并且，特别是 b) 将 Rubisco 激活酶研究扩展到包括硅藻，因为它们在 CO2 管理中被列为主要贡献者。该研究是可行的，因为： b) 已经完成了异质格玛 Rubisco 的广泛分析； c) 已记录了响应光提示的 Rubisco mRNA 产生模式； d) 异形抗体和硅藻 Rubisco 抗体已被证明会发生交叉反应； e) 已经对抗体标记的 Rubisco 进行了流式细胞术测量。虽然努力了解浮游植物中 Rubisco 激活酶对 Rubisco 的调节可能存在风险，但本研究将建立有色藻类的主要数据库，其中破译通过 Rubisco/Rubisco 激活酶相互作用进行无机碳加工的生物化学。当考虑到预测响应气候变化的光合作用性能时，这项研究的长期效益非常显着。