Institute of Biology, University of Leipzig, Johannisallee 23, D-04103 Leipzig, Germany.
Plant Cell Physiol. 2012 Dec;53(12):2153-62. doi: 10.1093/pcp/pcs144. Epub 2012 Oct 25.
Diatoms are the most successful biomass producers worldwide. Therefore, physiological and chemical methods to measure the cell response to a variety of abiotic factors are the focus of recent research. We used the two model diatoms Cyclotella meneghiniana and Skeletonema costatum for the development of Fourier transform infrared (FTIR) spectroscopy-based methods to measure simultaneously the elemental composition of the cells and their cell-specific physiological properties. The cells were grown in chemostat cultures to study the response of Si limitation. The model organisms showed different reactions in terms of their cell properties. Si limitation was accompanied by a drop in the growth rate, a reduced content in Si per cell and a decreased Si : C ratio. Furthermore, the C allocation pattern was changed in both diatoms under Si limitation, as shown by FTIR spectroscopy. Moreover, we used FTIR spectra to develop PLS (partial least square) regression methods to predict the Si content and the Si : C ratio for single as well as multiple species. All PLS regression models were validated by standard chemical methods and showed good prediction accuracy, with the coefficient of determination R(2) being ≥0.93. We could show that it is possible to monitor phytoplankton properties such as C allocation, the Si content and the Si : C ratio at the same time via FTIR spectroscopy.
硅藻是全球最成功的生物量生产者。因此，测量细胞对各种非生物因素的反应的生理和化学方法是最近研究的重点。我们使用两种模式硅藻（Cyclotella meneghiniana 和 Skeletonema costatum）来开发基于傅里叶变换红外（FTIR）光谱的方法，以同时测量细胞的元素组成及其特定的细胞生理特性。细胞在恒化器培养中生长，以研究硅限制的反应。模型生物在细胞特性方面表现出不同的反应。硅限制伴随着生长速率下降、每个细胞中的硅含量减少和硅：碳比降低。此外，FTIR 光谱显示，两种硅藻的 C 分配模式在硅限制下发生了变化。此外，我们使用 FTIR 光谱来开发 PLS（偏最小二乘）回归方法，以预测单个和多个物种的硅含量和硅：碳比。所有 PLS 回归模型均通过标准化学方法进行验证，显示出良好的预测准确性，决定系数 R(2)≥0.93。我们证明了通过 FTIR 光谱同时监测浮游植物特性，如 C 分配、硅含量和硅：碳比是可行的。
