Byloos Bo, Coninx Ilse, Van Hoey Olivier, Cockell Charles, Nicholson Natasha, Ilyin Vyacheslav, Van Houdt Rob, Boon Nico, Leys Natalie
Microbiology Unit, Belgian Nuclear Research Centre, SCK•CENMol, Belgium.
Center for Microbial Ecology and Technology, Ghent UniversityGhent, Belgium.
Front Microbiol. 2017 Apr 28;8:671. doi: 10.3389/fmicb.2017.00671. eCollection 2017.
Microbe-mineral interactions have become of interest for space exploration as microorganisms could be used to biomine from extra-terrestrial material and extract elements useful as micronutrients in life support systems. This research aimed to identify the impact of space flight on the long-term survival of CH34 in mineral water and the interaction with basalt, a lunar-type rock in preparation for the ESA spaceflight experiment, BIOROCK. Therefore, CH34 cells were suspended in mineral water supplemented with or without crushed basalt and send for 3 months on board the Russian FOTON-M4 capsule. Long-term storage had a significant impact on cell physiology and energy status (by flow cytometry analysis, plate count and intracellular ATP measurements) as 60% of cells stored on ground lost their cell membrane potential, only 17% were still active, average ATP levels per cell were significantly lower and cultivability dropped to 1%. The cells stored in the presence of basalt and exposed to space flight conditions during storage however showed less dramatic changes in physiology, with only 16% of the cells lost their cell membrane potential and 24% were still active, leading to a higher cultivability (50%) and indicating a general positive effect of basalt and space flight on survival. Microbe-mineral interactions and biofilm formation was altered by spaceflight as less biofilm was formed on the basalt during flight conditions. Leaching from basalt also changed (measured with ICP-OES), showing that cells release more copper from basalt and the presence of cells also impacted iron and magnesium concentration irrespective of the presence of basalt. The flight conditions thus could counteract some of the detrimental effects observed after the 3 month storage conditions.
微生物与矿物质的相互作用已成为太空探索的研究热点，因为微生物可用于从外星物质中进行生物采矿，并提取对生命支持系统有用的作为微量营养素的元素。本研究旨在确定太空飞行对CH34在矿泉水中长期存活的影响以及与玄武岩（一种月球类型的岩石）的相互作用，为欧洲航天局的太空飞行实验BIOROCK做准备。因此，将CH34细胞悬浮于添加或未添加粉碎玄武岩的矿泉水中，并搭载俄罗斯的FOTON - M4太空舱进行为期3个月的飞行。长期储存对细胞生理和能量状态有显著影响（通过流式细胞术分析、平板计数和细胞内ATP测量），因为地面储存的细胞中有60%失去了细胞膜电位，只有17%仍具有活性，每个细胞的平均ATP水平显著降低，可培养性降至1%。然而，在储存过程中存在玄武岩并暴露于太空飞行条件下的细胞，其生理变化较小，只有16%的细胞失去细胞膜电位，24%仍具有活性，导致更高的可培养性（50%），这表明玄武岩和太空飞行对细胞存活具有总体积极影响。太空飞行改变了微生物与矿物质的相互作用以及生物膜的形成，因为在飞行条件下玄武岩上形成的生物膜较少。玄武岩的浸出情况也发生了变化（通过电感耦合等离子体质谱法测量），表明细胞从玄武岩中释放出更多的铜，并且细胞的存在也会影响铁和镁的浓度，无论玄武岩是否存在。因此，飞行条件可以抵消3个月储存条件后观察到的一些有害影响。
