ATPase, alpha/beta subunit, nucleotide-binding domain, active site <p>This entry represents the alpha and beta subunits found in the F1, V1, and A1 complexes of F-, V- and A-ATPases, respectively (sometimes called the A and B subunits in V- and A-ATPases), as well as flagellar ATPase and the termination factor Rho. </p><p>This entry represents a 10 amino acid signature. The signature pattern contains two conserved serines. The first serine seems to be important for catalysis - in the ATPase alpha-chain at least - as its mutagenesis causes catalytic impairment. </p>