Purity >95% by SDS-PAGE. ackA catalyzes the formation of acetyl phosphate from acetate and ATP. This protein can also catalyze the reverse reaction. During anaerobic growth of the organism, this enzyme is also involved in the synthesis of most of the ATP formed catabolically. Recombinant E.coli ackA protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.