Abstract
F- and V-ATPases are unique bio- and nano-molecular rotary motors among many types of bioenergy-transducing machineries. The rotational catalysis of F1-ATPase has been investigated in detail, and the molecular mechanisms have been proposed on the basis of crystal structures of the complex and extensive single-molecule observation of the rotation. Recently, we have obtained crystal structures of bacterial V1-ATPase (A3B3 and A3B3DF complexes) with and without nucleotide. On the basis of these new structures, we present a novel model of the rotational catalytic mechanism for V1-ATPase, which is apparently different from those of F1-ATPases.
