Purification of vacuolar ATPase with bafilomycin C1 affinity chromatography

We have developed a fast and simple affinity purification method for vacuolar ATPases (V-ATPases) using bafilomycin C1 -coupled cellulose column. The purified protein from solubilized chicken medullary bone microsomal vesicles contains 8 subunits at sizes of 72, 65, 55, 41, 34, 20, 17 and 15 kDa. This subunit structure is typical to V-ATPases. Although the enzyme obtained is inactive, this method is useful in search of various isoforms of known V-ATPase subunits. We also present further evidence that the binding site of bafilomycin is located in the 17 kDa proteolipid subunit of V-ATPase.