The missing link between thermodynamics and structure in F1-ATPase.

ABSTRACT: F(1)F(o)-ATP synthase is the enzyme responsible for most of the ATP synthesis in living systems. The catalytic domain F(1) of the F(1)F(o) complex, F(1)-ATPase, has the ability to hydrolyze ATP. A fundamental problem in the development of a detailed mechanism for this enzyme is that it has not been possible to determine experimentally the relation between the ligand binding affinities measured in solution and the different conformations of the catalytic beta subunits (beta(TP), beta(DP), beta(E)) observed in the crystal structures of the mitochondrial enzyme, MF(1). Using free energy difference simulations for the hydrolysis reaction ATP+H(2)O --> ADP+P(i) in the beta(TP) and beta(DP) sites and unisite hydrolysis data, we are able to identify beta(TP) as the "tight" (K(D) = 10(-12) M, MF(1

SUBMITTER: Yang W 

PROVIDER: S-EPMC298694 | biostudies-literature | 2003 Feb

REPOSITORIES: biostudies-literature