Involvement of the Pta-AckA pathway in protein folding and aggregation

Acetyl phosphate is a central metabolite involved in a broad range of versatile cellular functions. Recently it was observed that in Escherichia coli the acetyl phosphate pathway is required for efficient ATP-dependent proteolysis. Deletion of the operon coding for acetyl phosphate metabolism (Delta ackApta) results in a very low cytoplasmic level of acetyl phosphate and impaired proteolysis. Here we show that the Delta ackApta mutation affects additional components of the protein quality control system. Thus, this deletion is accompanied by a decrease in protein refolding and rescue from aggregates. These results indicate the involvement of the acetyl phosphate pathway in chaperone capabilities, in addition to their effect on proteolysis. (C) 2008 Published by Elsevier Masson SAS.