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

FEBS Lett. 1993 Mar 29;320(1):17-22. doi: 10.1016/0014-5793(93)81648-j.

Abstract

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 A, b = 66.2 A, gamma = 104.2 degrees) 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.

MeSH terms

  • Animals
  • Cell Membrane / enzymology
  • Crystallization
  • Dogs
  • Hydrogen-Ion Concentration
  • Image Processing, Computer-Assisted
  • Kidney / enzymology*
  • Microscopy, Electron
  • Sodium-Potassium-Exchanging ATPase / chemistry*
  • Sodium-Potassium-Exchanging ATPase / metabolism
  • Sodium-Potassium-Exchanging ATPase / ultrastructure

Substances

  • Sodium-Potassium-Exchanging ATPase