Crystal structure of A3B3 complex of V-ATPase from Thermus thermophilus Academic Article uri icon

abstract

  • Vacuolar-type ATPases (V-ATPases) exist in various cellular membranes of many organisms to regulate physiological processes by controlling the acidic environment. Here, we have determined the crystal structure of the A(3)B(3) subcomplex of V-ATPase at 2.8 A resolution. The overall construction of the A(3)B(3) subcomplex is significantly different from that of the alpha(3)beta(3) sub-domain in F(o)F(1)-ATP synthase, because of the presence of a protruding 'bulge' domain feature in the catalytic A subunits. The A(3)B(3) subcomplex structure provides the first molecular insight at the catalytic and non-catalytic interfaces, which was not possible in the structures of the separate subunits alone. Specifically, in the non-catalytic interface, the B subunit seems to be incapable of binding ATP, which is a marked difference from the situation indicated by the structure of the F(o)F(1)-ATP synthase. In the catalytic interface, our mutational analysis, on the basis of the A(3)B(3) structure, has highlighted the presence of a cluster composed of key hydrophobic residues, which are essential for ATP hydrolysis by V-ATPases.

authors

  • Maher, Megan J
  • Akimoto, Satoru
  • Iwata, Momi
  • Nagata, Koji
  • Hori, Yoshiko
  • Yoshida, Masasuke
  • Yokoyama, Shigeyuki
  • Iwata, So
  • Yokoyama, Ken

publication date

  • December 2, 2009