title: Development of compartment for studies on the growth of protein crystals in space.
abstract: To clarify the growth mechanism of a protein crystal, it is essential to measure its growth rate with respect to the supersaturation. We developed a compartment (growth cell) for measuring the growth rate (<0.1 nm s(-1)) of the face of a protein crystal at a controlled supersaturation by interferometry over a period of half a year in space. The growth cell mainly consists of quartz glass, in which the growth solution and a seed crystal are enclosed by capillaries, the screw sample holder, and a helical insert. To avoid the destruction of the cell and the evaporation of the water from the solution inside the cell, we selected the materials for these components with care. The equipment was successfully used to examine the growth of a lysozyme crystal at a controlled supersaturation in space, where convection is negligible because of the microgravity environment, thereby advancing our understanding of the mechanism of protein crystal growth from solution. The technique used to develop the growth cell is useful not only for space experiments but also for kinetic studies of materials with very slow growth and dissolution rates (<10(-3) nm s(-1)).
authors.affiliation: Department of Earth Science, Graduate School of Science, Tohoku University, 6-3 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamazaki
authors.affiliation: Department of Earth Science, Graduate School of Science, Tohoku University, 6-3 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tsukamoto
authors.affiliation: Japan Aerospace Exploration Agency (JAXA), 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Yoshizaki
authors.affiliation: Advanced Engineering Services Co., Ltd., Tsukuba Mitsui Bldg., 1-6-1 Takezono, Tsukuba, Ibaraki 305-0032, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Fukuyama
authors.affiliation: Graduate School of Natural Sciences, Nagoya City University, 1 Yamamohata, Mizuho-cho, Mizuho-ku, Nagoya, Aichi 467-8501, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Miura
authors.affiliation: Japan Space Forum, 3-2-1 Surugadai, Chiyoda, Tokyo 101-0062, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Shimaoka
authors.affiliation: Olympus Optical Co., Hachioji, Tokyo 192-8507, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Maki
authors.affiliation: Department of Earth Science, Graduate School of Science, Tohoku University, 6-3 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Oshi
authors.affiliation: Institute of Low Temperature Science, Hokkaido University, Kita-19, Nishi-8, Kita-ku, Sapporo, Hokkaido 060-0819, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kimura
mesh_terms: D003460:Crystallization / Q000379:methods*; D005118:Extraterrestrial Environment; D007700:Kinetics; D011506:Proteins / Q000737:chemistry*
chemical_list: D011506:Proteins