Spaceflight Promotes Biofilm Formation by Pseudomonas aeruginosa

Abstract

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.

Tributyl tetradecyl phosphonium chloride for biofouling control in reverse osmosis processes

“…CLSM images were observed using a 40 × objective lens (C-APOCHROMAT 40 ×/1.20 W Korr M27; Carl Zeiss). Confocal images of green (live cells) and red (dead cells) fluorescence were observed simultaneously with the Z-stack mode [35,38]. In addition, three dimensional image stacks were conducted to analyze biofilm density (μm 3 /μm 2 ) and average thickness of biofilm (μm) using the COMSTAT program [39] of ImageJ software [40].…”

Selling space colonization and immortality: A psychosocial, anthropological critique of the rush to colonize Mars

“…Negative effects of outer space on human health have also occurred with the effects of microbial communities [58], bone loss [63], fractures [62], problems with perchlorates and gypsum [52], eye problems including disc edema, globe flattening, choroidal folds, and hyperopic shifts [67], just to name a few. NASA's Human Research Road Map [80] lists several detailed studies on human factor problems in space.…”

Invited Review Article: Advanced light microscopy for biological space research

“…Spaceflight has been shown to increase biofilm biomass, thickness, and three-dimensional organization compared to ground conditions. 33 In this context, it is worth noting that biofilms were an abundant nuisance on the Russian Mir space station and are still a challenge on the International Space Station (ISS). Similarly, two-dimensional mammalian cell monolayers cultured on hard and flat substrates do not experience the same biochemical or mechanical cues as those found in real tissues.…”