Department of Chemical & Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA.
PLoS One. 2013 Apr 29;8(4):e62437. doi: 10.1371/journal.pone.0062437. Print 2013.
Understanding the effects of spaceflight on microbial communities is crucial for the success of long-term, manned space missions. Surface-associated bacterial communities, known as biofilms, were abundant on the Mir space station and continue to be a challenge on the International Space Station. The health and safety hazards linked to the development of biofilms are of particular concern due to the suppression of immune function observed during spaceflight. While planktonic cultures of microbes have indicated that spaceflight can lead to increases in growth and virulence, the effects of spaceflight on biofilm development and physiology remain unclear. To address this issue, Pseudomonas aeruginosa was cultured during two Space Shuttle Atlantis missions: STS-132 and STS-135, and the biofilms formed during spaceflight were characterized. Spaceflight was observed to increase the number of viable cells, biofilm biomass, and thickness relative to normal gravity controls. Moreover, the biofilms formed during spaceflight exhibited a column-and-canopy structure that has not been observed on Earth. The increase in the amount of biofilms and the formation of the novel architecture during spaceflight were observed to be independent of carbon source and phosphate concentrations in the media. However, flagella-driven motility was shown to be essential for the formation of this biofilm architecture during spaceflight. These findings represent the first evidence that spaceflight affects community-level behaviors of bacteria and highlight the importance of understanding how both harmful and beneficial human-microbe interactions may be altered during spaceflight.
了解太空飞行对微生物群落的影响对于长期载人航天任务的成功至关重要。表面相关的细菌群落，即生物膜，在 Mir 空间站上大量存在，并且在国际空间站上仍然是一个挑战。由于在太空飞行中观察到免疫功能受到抑制，与生物膜发展相关的健康和安全危害尤其令人关注。虽然微生物的浮游培养物表明太空飞行会导致生长和毒性增加，但太空飞行对生物膜发展和生理学的影响仍不清楚。为了解决这个问题，在两次航天飞机亚特兰蒂斯任务期间培养了铜绿假单胞菌：STS-132 和 STS-135，并对太空飞行期间形成的生物膜进行了表征。与正常重力对照相比，观察到太空飞行会增加活细胞数量、生物膜生物量和厚度。此外，在太空中形成的生物膜表现出一种柱状和伞状结构，在地球上尚未观察到。在太空中，生物膜数量的增加和新型结构的形成被观察到与培养基中的碳源和磷酸盐浓度无关。然而，鞭毛驱动的运动被证明是在太空中形成这种生物膜结构所必需的。这些发现代表了第一个证据，表明太空飞行会影响细菌的群落行为，并强调了了解在太空飞行期间有害和有益的人类微生物相互作用可能如何改变的重要性。
