Crystals (Feb 2019)

Very Low Nucleation Rates of Glucose Isomerase Crystals under Microgravity in the International Space Station

  • Yoshihisa Suzuki,
  • Takahisa Fujiwara,
  • Katsuo Tsukamoto,
  • Seijiro Fukuyama,
  • Taro Shimaoka,
  • Kazuma Tsuchiya,
  • Ai Ninomiya,
  • Yumiko Murakumo,
  • Akiho Ikeuchi,
  • Hitomi Minamizono,
  • Tomokazu Yamazaki,
  • Takehiko Sone,
  • Tetsuya Sakashita,
  • Masae Nagai,
  • Yasutomo Arai

DOI
https://doi.org/10.3390/cryst9020090
Journal volume & issue
Vol. 9, no. 2
p. 90

Abstract

Read online

In situ observation of the nucleation and growth of glucose isomerase (GI) crystals under microgravity was conducted using an optical microscope during the first flight of the Advanced Nano Step project undertaken in the International Space Station (ISS). Very low apparent nucleation rates (J’) of GI crystals in the solution and on the substrate of the growth container were confirmed compared with those on the ground. In particular, J’ of GI crystals in the solution were a few times lower than that on the substrate. The growth rates (R) of the {101} faces of GI crystals on the substrate and the apparent growth rates (R’) in the solution were measured. The very low nucleation rates allowed us to successfully measure R at a very high supersaturation region (up to ln(C/Ce) = 6), at which R cannot be measured on the ground.

Keywords