PfA-M1 is minimally associated with FV fractions. A. P. falciparum food vacuole fractions were isolated as shown in the schematic diagram and in the Methods section. B. Fractions A to F were analysed for the presence of marker proteins. Equivalent amounts of proteins were loaded for each fraction (corresponding to 4 × 107 iRBC per lane), and immunoblotted with anti-MAP1 antibodies  to reveal PfA-M1, or antibodies against Plasmepsin 1 (Plas1), PfSERP (SERP) and PfAldolase  (Ald) as controls. The numbers on the left indicate Mw in kDa. The densitometric analysis of these immunoblots is presented as Table 1.