Journal of Synchrotron Radiation

Volume 15, Part 3 (May 2008)

diffraction structural biology

J. Synchrotron Rad. (2008). 15, 269-272 [ doi:10.1107/S0909049508001842 ]

Protein crystallization in a 100 nl solution with new stirring equipment

S. Maki, R. Murai, H. Y. Yoshikawa, T. Kitatani, S. Nakata, H. Kawahara, H. Hasenaka, A. Kobayashi, S. Okada, S. Sugiyama, H. Adachi, H. Matsumura, K. Takano, S. Murakami, T. Inoue, T. Sasaki and Y. Mori

Abstract: To investigate quantitatively the effects of stirring on protein crystallization, a new stirring system which can agitate a protein solution, 100 nl, by providing Hagen-Poiseuille flow has been successfully developed. In addition, this new stirring system provides flow with a well defined pattern and velocity. Using this system, hen egg-white lysozyme was crystallized in 100-200 nl solutions while being stirred. The optimum stirring conditions for lysozyme crystals have been explored by evaluating the Reynolds (Re) number and the crystals obtained. Intermittent flow, as well as a low Re number, was found to contribute significantly to the growth of a smaller number of larger crystals.

Keywords: lysozyme; low-Reynolds-number flow; stirring method; syringe pump; microcapillary; thixotropy.