Specific activities reported in nmol/min/mg for purified and lipid/detergent reactivated Spf1p with the conditions for individual experiments shown.

Star indicate activity measurements using radiolabeled ATP32, C12E10: Polyoxyethylene(10)dodecyl Ether, OG: n-Octyl-β-D-Glucopyranoside, PC/POPC: phosphatidylcholine and n.r.: not reported. For comparison polyamine stimulated activity of lipid activated ATP13A2 is ~150 nmol/min/mg [2] and for Ypk9p ~1.000 nmol/min/mg [18] both at 37⁰C, phosphatidylserine stimulated activity of the lipid flippase ATP8A1 is ~100.000 nmol/min/mg at 37⁰C [36], the activated state of the Pma1p H+ ATPase is reported at ~12.000 nmol/min/mg at 30⁰C [37] and activity for SERCA and SPCA Ca2+ ATPases are reported at ~12.000 nmol/min/mg and ~2500 nmol/min/mg respectively in proteoliposomes [38].