Identification of alpha-subunit Lys201 and beta-subunit Lys155 at the ATP-binding sites in Escherichia coli F1-ATPase.

Binding of about 1 mol of adenosine triphosphopyridoxal to Escherichia coli F1-ATPase resulted in the nearly complete inactivation of the enzyme [(1987) J. Biol. Chem. 262, 7686-7692]. About two thirds of the label was bound to the alpha-subunit, and the rest to the beta-subunit. The present study revealed that Lys201 in the alpha-subunit and Lys155 in the glycine-rich region of the beta-subunit are the major sites labeled with this reagent. Thus, these two residues might be located close to the gamma-phosphate of the bound ATP.