HS-AFM imaging of α3β3 subcomplex
of F1-ATPase under different nucleotide states. (a) Crystal
structure of α3β3γ subcomplex.
The α-, β-, and γ-subunits are shown in cyan, pink,
and yellow, respectively. (b) Typical HS-AFM image of α3β3 subcomplex immobilized on a chemically
treated mica surface without nucleotide (150 × 150 pixels; imaging
rate 1 fps). (c) Filtered HS-AFM image of C-terminal side of the α3β3 subcomplex without nucleotide. (d) C-terminal
side of crystal structure of the nucleotide-free α3β3 subcomplex. The α and β subunits
are colored in cyan and pink, respectively. The C-terminal DELSEED
motif of the β subunits corresponding to the high protruding
portions is highlighted in red. (e) Simulated AFM image constructed
from the structure in (d). (f) Filtered AFM image of the N-terminal
side of the α3β3 subcomplex without
nucleotides. (g) N-terminal side of the crystal structure of the α3β3 subcomplex. (h) Simulated AFM image constructed
from the structure in (g). (i) Filtered AFM image of the C-terminal
side of the α3β3 subcomplex at 1
mM AMP-PNP. (j) Crystal structure of the α3β3 subcomplex with bound nucleotides. This structure is obtained
by removing γ from the crystal structure of α3β3γ subcomplex. (k) Simulated AFM image constructed
from the structure in (j).