First ever cellulose synthesis in space

Cellulose is the main substance in the walls of plant cells, helping plants to remain stiff and upright. In nature, cellulose is decomposed at normal temperature and pressure by an enzyme called cellulase, produced by various microorganisms and used as a nutrient source for various species.

The cellulose was synthesised in a small incubator developed by JAMSS on the International Space Station (ISS), using an enzyme sample prepared by Associate Professor Igarashi and colleagues. The high quality protein crystal growth service “Kirara” is provided by Japan Manned Space Systems Corporation (JAMSS) and operated in our ICE Cubes Facility.  The cellulose was molecularly grown over a period of approximately one month on-board.

After being successfully returned to ground, the crystals grown in space as part of the “Kirara” mission of Dec-2019 have been analysed by the research team lead by Dr. Naoki Sunagawa and Associate Professor Kiyohiko Igarashi from the Graduate School of Agricultural and Life Sciences, the University of Tokyo. At ground conditions, the cellulose synthesised by enzyme is precipitated by gravity in vitro. For the first time in the world, the attempt was made to synthesise cellulose enzymatically in space and the resulting uniform cellulose has been found to be different from cellulose precipitated on the ground.

This achievement has expanded the possibilities which Kirara’s services can provide not only to drug discovery support, but also to the wide field of materials.