Figure 4. Timeline of developments from folding proteins to membrane motors.

From left to right folding individual proteins (1997) and maintaining the molecular chaperone GroEL (far left) to instrumental designs for a high-mass quadrupole (top) and our first IM experiments (2005) showing separation of complexes with differing topologies but the same mass. Collection of GroEL soft-landed onto an EM grid located within the flight path of the beam. Release of membrane proteins into the gas phase led to preservation of an intact rotary ATPase (top) and fluctuations and binding of lipids and drugs to the ABC transporter P-gp as well as the first X-ray structure of the ammonia channel with lipids that stabilise the structure in the gas phase (2004).