Ewald Jennifer Christina, Heux Stéphanie, Zamboni Nicola
Institute of Molecular Systems Biology, ETH Zurich, Wolfgang-Pauli Strasse 16, 8093 Zurich, Switzerland.
Anal Chem. 2009 May 1;81(9):3623-9. doi: 10.1021/ac900002u.
Metabolomics is a founding pillar of quantitative biology and a valuable tool for studying metabolism and its regulation. Here we present a workflow for metabolomics in microplate format which affords high-throughput and yet quantitative monitoring of primary metabolism in microorganisms and in particular yeast. First, the most critical step of rapid sampling was adapted to a multiplex format by using fritted 96-well plates for cultivation, which ensure fast sample transfer and permit us to use well-established quenching in cold solvents. Second, extensive optimization of large-volume injection on a GC/TOF instrument provided the sensitivity necessary for robust quantification of 30 primary metabolites in 0.6 mg of yeast biomass. The metabolome profiles of baker's yeast cultivated in fritted well plates or in shake flasks were equivalent. Standard deviations of measured metabolites were between 10% and 50% within one plate. As a proof of principle we compared the metabolome of wild-type Saccharomyces cerevisiae and the single-deletion mutant Delta sdh1, which were clearly distinguishable by a 10-fold increase of the intracellular succinate concentration in the mutant. The described workflow allows the production of large amounts of metabolome samples within a day, is compatible with virtually all liquid extraction protocols, and paves the road to quantitative screens.
代谢组学是定量生物学的基石,也是研究代谢及其调控的重要工具。本文介绍了一种微孔板形式的代谢组学工作流程,该流程能够对微生物尤其是酵母中的初级代谢进行高通量且定量的监测。首先,通过使用烧结96孔板进行培养,将快速采样这一最关键步骤调整为多重形式,这种板确保了快速的样品转移,并使我们能够在冷溶剂中采用成熟的淬灭方法。其次,在气相色谱/飞行时间质谱仪上对大体积进样进行了广泛优化,从而为在0.6毫克酵母生物质中对30种初级代谢物进行可靠定量提供了所需的灵敏度。在烧结孔板或摇瓶中培养的面包酵母的代谢组图谱是等效的。在一个板内,所测代谢物的标准偏差在10%至50%之间。作为原理验证,我们比较了野生型酿酒酵母和单缺失突变体Δsdh1的代谢组,二者通过突变体中细胞内琥珀酸浓度增加10倍而明显区分开来。所描述的工作流程能够在一天内生成大量代谢组样品,几乎与所有液体提取方案兼容,并为定量筛选铺平了道路。