Aromatic rings of tyrosine residues at adenine nucleotide binding sites of the beta subunits of F1-ATPase are not necessary for ATPase activity

Abstract

Using site-directed mutagenesis, Tyr-307, Tyr-341, or Tyr-364, supposedly located at the adenine nucleotide binding site(s) of the beta subunits of F1-ATPase from the thermophilic bacterium PS3, was replaced with Phe or Cys. The alpha 3 beta 3 complexes reconstituted from the alpha subunits and individual mutant beta subunits hydrolyzed ATP. Thus, neither the hydroxyl groups nor the aromatic rings in these positions are required for ATPase activity of F1-ATPase.