Fig. 7.

Vanadate inhibition of ATPase activity from an ER-enriched fraction purified from K616 cells either expressing M535L (closed symbols) or transformed with the empty pYES2 vector (open symbols). ATPase activity, assayed in the presence of increasing concentrations of vanadate, is expressed as a per cent of the activity measured in the absence of vanadate (350 nmol Pi mg⁻¹ protein min⁻¹ for M535L and 160 nmol Pi mg⁻¹ protein min⁻¹ for empty vector).