Mishek Henry P, Stock Stephen A, Florick Jacqueline D E, Blomberg Wilson R, Franke Josef D
Creighton University, Biology Department, 2500 California Plaza, Omaha, NE 68310, USA.
Creighton University, Biology Department, 2500 California Plaza, Omaha, NE 68310, USA.
J Microbiol Methods. 2018 Feb;145:40-46. doi: 10.1016/j.mimet.2017.12.010. Epub 2017 Dec 29.
We experimentally determined minimal media requirements for Gemmata obscuriglobus, a Gram-negative Planctomycete bacteria with several unusual physiological features. We find that supplementing media with the usual vitamins solution does not improve viability, but does result in an increased growth rate in liquid cultures and a larger colony size on agar plates. By systematically including individual vitamins, or omitting individual vitamins, from media we find that the addition of only two vitamins, biotin and cyanocobalamin, are sufficient to restore colony growth to comparable rates as other commonly used media. Overall, our findings define minimal media requirements for the culturing of this low-nutrient organism. One of G. obscuriglobus unusual physiological features is the ability to internalize fully-folded proteins. Using fluorescence microscopy and flow cytometery we show that this physiological behavior is dependent on media state and composition. The percentage of cells exhibiting internalization of GFP when grown on a particular, solid minimal medium is far greater than cells grown in liquid medium of similar composition or other solid media with different compositions.
我们通过实验确定了暗球菌（Gemmata obscuriglobus）的基本培养基需求，暗球菌是一种革兰氏阴性浮霉菌门细菌，具有若干不同寻常的生理特征。我们发现，在培养基中添加常用的维生素溶液并不能提高其活力，但确实会使液体培养物中的生长速率提高，且在琼脂平板上形成的菌落更大。通过在培养基中系统地添加或省略单个维生素，我们发现仅添加生物素和钴胺素这两种维生素就足以使菌落生长速率恢复到与其他常用培养基相当的水平。总体而言，我们的研究结果确定了培养这种低营养生物的基本培养基需求。暗球菌不同寻常的生理特征之一是能够内化完全折叠的蛋白质。利用荧光显微镜和流式细胞术，我们表明这种生理行为取决于培养基的状态和组成。在特定的固体基本培养基上生长时，表现出绿色荧光蛋白内化的细胞百分比远高于在成分相似的液体培养基或其他成分不同的固体培养基上生长的细胞。
