Iron Limitation and Phytoplankton Photosynthesis: Research Fellowship in Marine Biotechnology

铁限制和浮游植物光合作用：海洋生物技术研究奖学金

• 批准号: 8915084
• 负责人: Richard Geider
• 金额: $ 3.94万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-06-01 至 1991-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8915084&HistoricalAwards=false
• 关键词: Iron; Limitation; Phytoplankton; Photosynthesis; Research

Recent evidence has indicated that the availability of iron may limit phytoplankton biomass and primary production in many oceanographic regions. Iron is a key component of the photosynthetic electron transport chain; reductions in the rate and efficiency of photosynthesis are expected when phytoplankton growth is iron-limited. In the fellowship research, biophysical, biochemical and immunological techniques will be used to examine the phenotypic response of the photosynthetic apparatus of marine phytoplankton to iron deficiency under controlled conditions in iron-limited chemostat cultures. Interspecific comparisons will be made between organisms from two taxonomic groups, a diatom and a coccolothophorid. The concentrations of the PS I reaction center chlorophyll (P700), the cytochrome b complex and the soluble electron carriers ferredoxin and flavodoxin will be measured spectrophotometrically. Oxygen flash yields will be used to determine the concentration of active PS II reaction centers, and flash fluorescence techniques will be used to determine the fraction of total PS II reaction centers which are active. Polyclonal antibodies from marine algae or higher plants will be used to determine the relative abundances of the carboxylating enzyme ribulose biphosphate carboxylase, the thylakoid ATP synthetase, several components of the PS II reaction center complex and light harvesting complex proteins.

最近的证据表明，铁的可用性可能限制许多海洋区域的浮游植物生物量和初级生产。铁是光合作用电子传递链的关键组成部分；当浮游植物的生长受到铁的限制时，光合作用的速率和效率会降低。在奖学金研究中，生物物理、生化和免疫学技术将被用于研究海洋浮游植物光合器官对铁缺乏的表型反应。种间比较将在两个分类群，硅藻和球藻之间进行。用分光光度法测定PS I反应中心叶绿素（P700）、细胞色素b复合物和可溶性电子载体铁氧还蛋白和黄氧还蛋白的浓度。氧闪率将用于确定活性PS II反应中心的浓度，闪光荧光技术将用于确定活性PS II反应中心的比例。来自海藻或高等植物的多克隆抗体将用于测定羧化酶二磷酸核酮糖羧化酶、类囊体ATP合成酶、PS II反应中心复合物和光收获复合物蛋白的几个组分的相对丰度。