Inomura Keisuke, Omta Anne Willem, Talmy David, Bragg Jason, Deutsch Curtis, Follows Michael J
School of Oceanography, University of Washington, Seattle, WA, United States.
Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United States.
Front Microbiol. 2020 Feb 28;11:86. doi: 10.3389/fmicb.2020.00086. eCollection 2020.
We present a model of the growth rate and elemental stoichiometry of phytoplankton as a function of resource allocation between and within broad macromolecular pools under a variety of resource supply conditions. The model is based on four, empirically-supported, cornerstone assumptions: that there is a saturating relationship between light and photosynthesis, a linear relationship between RNA/protein and growth rate, a linear relationship between biosynthetic proteins and growth rate, and a constant macromolecular composition of the light-harvesting machinery. We combine these assumptions with statements of conservation of carbon, nitrogen, phosphorus, and energy. The model can be solved algebraically for steady state conditions and constrained with data on elemental stoichiometry from published laboratory chemostat studies. It interprets the relationships between macromolecular and elemental stoichiometry and also provides quantitative predictions of the maximum growth rate at given light intensity and nutrient supply rates. The model is compatible with data sets from several laboratory studies characterizing both prokaryotic and eukaryotic phytoplankton from marine and freshwater environments. It is conceptually simple, yet mechanistic and quantitative. Here, the model is constrained only by elemental stoichiometry, but makes predictions about allocation to measurable macromolecular pools, which could be tested in the laboratory.
我们提出了一个浮游植物生长速率和元素化学计量学的模型，该模型是在各种资源供应条件下，作为大分子库之间和内部资源分配的函数。该模型基于四个得到实验支持的基石假设：光与光合作用之间存在饱和关系、RNA/蛋白质与生长速率之间存在线性关系、生物合成蛋白质与生长速率之间存在线性关系，以及光捕获机制的大分子组成恒定。我们将这些假设与碳、氮、磷和能量守恒的表述相结合。该模型可以通过代数方法求解稳态条件，并根据已发表的实验室恒化器研究中的元素化学计量学数据进行约束。它解释了大分子和元素化学计量学之间的关系，还提供了给定光强度和养分供应速率下最大生长速率的定量预测。该模型与来自多项实验室研究的数据集兼容，这些研究对来自海洋和淡水环境的原核和真核浮游植物进行了表征。它在概念上很简单，但具有机械性和定量性。在这里，该模型仅受元素化学计量学的约束，但对可测量的大分子库的分配进行了预测，这些预测可以在实验室中进行测试。
