Two-dimensional crystals of the mitochondrial ATP synthase up to 0.4 m
u m in size were obtained from the detergent-lipid-protein micelles by
detergent dialysis. A projected map of the negatively stained crystal
was calculated from electron microscopical images by the Fourier-filt
ering procedure at about 2.8 nm resolution. The unit cell (with not mo
re than two ATP synthase molecules) has the following parameters: a =
13.0 nm, b = 25.6 nm and gamma = 86 degrees. Two alternative models fo
r the crystal structural organization were suggested, viz. with one or
two protein molecules per unit cell.