Cover Picture: Single DNA Rotaxanes of a Transmembrane Pore Protein (Angew. Chem. Int. Ed. 23/2004)

A single rotaxane structure created by threading and capturing a DNA–poly(ethylene glycol) (DNA–PEG) strand inside an α‐hemolysin (α‐HL) transmembrane pore protein is described by M. R. Ghadiri and co‐workers on page 3063 ff. The DNA–α‐HL rotaxanes exhibit a reversible two‐state switching capacity that depends on the applied transmembrane potential, the orientation, and the method of threading and capture used. Functional rotaxanes might provide a means for critically assessing the feasibility of the pore‐mediated single‐molecule DNA sequencing hypothesis.