Page 60 - International Space Station Benefits for Humanity, 3rd edition.

as well as the ratio of impurities through the diffusion/ space using the commercially available MinION
capture coefficient of protein. Under microgravity DNA Sequencer, and demonstrating the ability for
conditions, convection and sedimentation are sequencing applications in space, including disease
suppressed; therefore, diffusion areas are maintained, diagnosis and environmental monitoring during
the density around the crystals decreases, the spaceflight (Castro-Wallace et al., 2017).
crystals can grow slowly, the capture of impurities and
microcrystal decreases, and high-quality protein crystals
can be better obtained. These methods contribute to Plant Biology and Bioregenerative
the complex process of drug discovery by revealing Life Support
disease-related protein structure, and the production Results from plant growth on the space station have
of new catalysts for the environmental and energy come from experiments designed for developing
industries (Sakamoto et al., 2015; Itoh et al., 2016; bioregenerative food production systems for the space
Kinoshita et al., 2017). station and for future long-duration exploration missions.
In the process, scientists have gained an understanding
of some of the basic processes of how plants grow on
Earth, and challenged existing scientific theories.
One such experiment made unique observations to
attempt to elucidate the underlying mechanisms of
circumnutation—a circular movement of growing stem
first described by Charles Darwin in 19th century.
The unique environment of the space station allowed
these experiments to be developed where gravity
could be an independent, changeable variable,
unlike on Earth. As a result, scientists observed that
circumnutation is a result of interplay between the
plant’s own internal signals, gravity and light—not just
gravity alone, as had been theorized (Johnsson et al.,
2009; Solheim et al., 2009). Studies of arabidopsis
showed that the patterns of root waving and skewing
during sprouting are similar on Earth as they are in
Hemoglobin protein crystal grown on the space space, demonstrating for the first time that gravity
station (left) and on Earth (right). is not a significant factor for these patterns of root
Image credit: JAXA growth. Images also revealed that in the absence of
gravity with the presence of directional light, roots
grew by skewing to the right, as opposed to growing
New capabilities in biological analyses that have been straight down, away from the light source (Amalfitano
developed and tested on the space station will enable et al., 2012). Investigators were able to determine the
future breakthroughs in molecular and genetics research gravity perception thresholds of plants when grown
in space. The first test of a miniaturized flow cytometer under various gravitational levels on the centrifuge on
in microgravity was performed on the space station to the space station (Driss-Ecole et al., 2008); another
enable real-time onboard biological analyses (Dubeau-
Laramée et al., 2014). Flow cytometry focuses fluids
(blood or other body fluids) into a controlled stream that
enables researchers to quantify specific molecules and The unique environment of the space
monitor physiological and cellular activity. Another station allowed these experiments to
instrument sent to the space station proved that it
can successfully amplify RNA to allow investigators to be developed where gravity could be
conduct molecular biology investigations that provide an independent, changeable variable,
insight into transient changes in gene expression seen
only during microgravity exposure (Parra et al., 2017). unlike on Earth.
In other groundbreaking experiments on the space
station, DNA was sequenced for the first time in

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