A pH induced two‐dimensional crystal of membrane‐bound Na+,K+‐ATPase of dog kidney

FEBS Letters

Fujiyoshi, Yoshinori¹  Tahara, Yoshikazu³  Kimura, Yoshiaki¹  Ohnishi, Shun-ichi³  Hayashi, Yutaro² 

[1] Protein Engineering Research Institute, 6-2-3 Furuedai, Suita, Osaka 565, Japan;Department Biochemistry, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181, Japan;Department of Biophysics, Faculty of Science, Kyoto University, Sakyo-ku, Kyoto 606, Japan

关键词: Sodium potassium adenosine triphosphatase (Na+;    K+-ATPase);    Two-dimensional crystallization;    Ice-embedding technique;    Electron cryo-microscopy;    Computer assisted image processing;   

DOI  :  10.1016/0014-5793(93)81648-J

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Two-dimensional crystals of membrane-bound Na⁺,K⁺-ATPase were formed in acidic media and their qualities were investigated by electron cryo-microscopy as well as by conventional electron microscopy. At pH 4.8 in sodium citrate buffer, the best crystallization condition, more than 80% of membranes formed crystals. The high ratio allowed high-resolution images to be taken by electron cryo-microscopy. Image processing revealed that they had unique lattice constants (a = 108.7 Å, b = 66.2 Å, γ = 104.2°) and had few defects in the crystalline arrays. The reconstituted Fourier map of the ice-embedded crystal showed that there are two high contrast parts in one unit cell.

【 授权许可】

Unknown