Self‐assembly of ATP synthase subunit c rings

Abstract
Subunit c of the H+ transporting ATP synthase is an essential part of its membrane domain that participates in transmembrane proton conduction. The annular architecture of the subunit c from different species has been previously reported. However, little is known about the type of interactions that affect the formation of c‐rings in the ATPase complex. Here we report that subunit c over‐expressed in Escherichia coli and purified in non‐ionic detergent solutions self‐assembles into annular structures in the absence of other subunits of the complex. The results suggest that the ability of subunit c to form rings is determined by its primary structure.