On a Dynamic Balance Theory of Photosynthetic Pigment Regulation in Unicellular Algae: Tests of a Novel Hypothesis

P.I.：Kana，Todd M.提案编号：96-33633标题：关于单细胞藻类光合色素调节的动态平衡理论：新假说的检验摘要微藻光合色素沉积的环境控制被假设为依赖于围绕光系统II动态运行的简单控制机制。50多年来，研究人员一直未能弄清光合色素的光驯化机制。根据光合作用装置在恒定和波动环境中的一般行为，描述了光驯化的“动态平衡”理论。这一新颖的理论首次解释了颜料浓度如何在广泛的光、营养和温度环境中进行优化。提出的研究将直接检验动平衡理论。调查的目标是四种不同分类的微藻。不同光适应条件下的受控生长实验将为相关的光合作用反应、色素作用和光系统II的动态变化提供基础。预计对该理论的实验支持将导致结合其他已知的光合作用调节机制的模型的发展，从而导致对光合作用的限制和光合作用有机体中的能量平衡机制的更广泛的认识。

P.I. : KANA, Todd M. Proposal No: 96-33633 Title: On a Dynamic Balance Theory of Photosynthetic Pigment Regulation in Unicellular Algae: Tests of a Novel Hypothesis ABSTRACT Environmental control of photosynthetic pigmentation in microalgae is hypothesized to depend on a simple control mechanism operating around photosystem II dynamics. The mechanisms responsible for photoacclimation of photosynthetic pigments have eluded researchers for more than 5 decades. A "dynamic balance" theory of photoacclimation is described based on general behavior of the photosynthetic apparatus in constant and fluctuating environments. This novel theory is the first to explain how pigment concentrations are optimized over a broad range of light, nutrient, and temperature environments. The proposed research will directly test the dynamic balance theory. Four taxonomically diverse microalgal species are targeted for investigations. Controlled growth experiments under differing photoacclimative conditions will provide a basis for relating photosynthetic response, pigmentation, and photosystem II dynamics. It is anticipated that experimental support for the theory will lead to the development of models combining other known photosynthetic regulatory mechanisms, resulting in a more general appreciation of constraints on photosynthesis and mechanisms of energy balance in photosynthetic organisms.