Research Division Biochemical Engineering, Institute of Chemical, Environmental and Bioscience Engineering, Faculty of Technical Chemistry, TU Wien, Vienna, Austria.
Center for Biotechnology (CeBiTec), Universität Bielefeld, Bielefeld, Germany.
J Biotechnol. 2019 Aug 10;301:56-67. doi: 10.1016/j.jbiotec.2019.04.028. Epub 2019 May 31.
The thermoacidophilic Crenarchaeon Sulfolobus acidocaldarius is an important model organism for Archaea and genetic systems are well established. To date, the organism is routinely cultivated on complex media based on protein hydrolysates and no common defined medium is established. In this work we address this lack of a standardized defined medium and replaced the complex protein hydrolysate with sodium glutamate as primary substrate. Starting from an existing medium formulation we stepwise managed to improve the medium regarding formation of precipitates, buffer capacity, concentration of basal salts and trace elements, and optimized growth rates. The differences on the cellular level between the original medium and our new formulation, called VD Medium, were investigated by comparative gene expression analysis and significant differences were discussed. The final formulation of the VD Medium contains 1.75 g/L Na-glutamate, 3 g/L D-glucose and 0.5 g/L citric acid as carbon sources. Using the described medium for the cultivation of S. acidocaldarius DSM 639 in shake flasks yields 1.1 g/L dry cell weight (OD = 1.7) after a typical incubation time of 95 h with an overall biomass yield of 0.33 g/g.
嗜热嗜酸古菌 Sulfolobus acidocaldarius 是古菌和遗传系统的重要模式生物，已有成熟的研究体系。目前，该生物通常在基于蛋白水解物的复杂培养基上进行常规培养，尚未建立通用的定义明确的培养基。在这项工作中，我们针对缺乏标准化定义培养基的问题，用谷氨酸钠替代复杂的蛋白水解物作为主要底物。从现有的培养基配方开始，我们逐步改进了培养基的沉淀形成、缓冲能力、基础盐和微量元素的浓度，并优化了生长速率。通过比较基因表达分析，研究了原始培养基和我们称为 VD 培养基的新配方在细胞水平上的差异，并讨论了显著差异。VD 培养基的最终配方包含 1.75 g/L Na-谷氨酸、3 g/L D-葡萄糖和 0.5 g/L 柠檬酸作为碳源。使用所描述的培养基在摇瓶中培养 S. acidocaldarius DSM 639，在典型的 95 小时孵育后，可得到 1.1 g/L 的干细胞重量（OD=1.7），总生物质产率为 0.33 g/g。
