Verbeelen Tom, Fernandez Celia Alvarez, Nguyen Thanh Huy, Gupta Surya, Aarts Raf, Tabury Kevin, Leroy Baptiste, Wattiez Ruddy, Vlaeminck Siegfried E, Leys Natalie, Ganigué Ramon, Mastroleo Felice
Nuclear Medical Applications, Belgian Nuclear Research Centre (SCK CEN), Boeretang 200, 2400, Mol, Belgium.
Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
NPJ Microgravity. 2024 Jan 10;10(1):3. doi: 10.1038/s41526-024-00345-z.
Regenerative life support systems (RLSS) will play a vital role in achieving self-sufficiency during long-distance space travel. Urine conversion into a liquid nitrate-based fertilizer is a key process in most RLSS. This study describes the effects of simulated microgravity (SMG) on Comamonas testosteroni, Nitrosomonas europaea, Nitrobacter winogradskyi and a tripartite culture of the three, in the context of nitrogen recovery for the Micro-Ecological Life Support System Alternative (MELiSSA). Rotary cell culture systems (RCCS) and random positioning machines (RPM) were used as SMG analogues. The transcriptional responses of the cultures were elucidated. For CO-producing C. testosteroni and the tripartite culture, a PermaLife PL-70 cell culture bag mounted on an in-house 3D-printed holder was applied to eliminate air bubble formation during SMG cultivation. Gene expression changes indicated that the fluid dynamics in SMG caused nutrient and O limitation. Genes involved in urea hydrolysis and nitrification were minimally affected, while denitrification-related gene expression was increased. The findings highlight potential challenges for nitrogen recovery in space.
再生生命支持系统（RLSS）在实现长途太空旅行的自给自足方面将发挥至关重要的作用。将尿液转化为液态硝酸盐基肥料是大多数RLSS中的关键过程。本研究描述了模拟微重力（SMG）对睾丸酮丛毛单胞菌、欧洲亚硝化单胞菌、维氏硝化杆菌以及这三种菌的三方培养物的影响，这是在微生态生命支持系统替代方案（MELiSSA）的氮回收背景下进行的。旋转细胞培养系统（RCCS）和随机定位机（RPM）被用作SMG模拟物。阐明了培养物的转录反应。对于产生一氧化碳的睾丸酮丛毛单胞菌和三方培养物，使用安装在内部3D打印支架上的PermaLife PL - 70细胞培养袋，以消除SMG培养过程中的气泡形成。基因表达变化表明，SMG中的流体动力学导致营养物质和氧气限制。参与尿素水解和硝化作用的基因受到的影响最小，而与反硝化作用相关的基因表达增加。这些发现突出了太空氮回收的潜在挑战。
