Highlights from recently determined structures of membrane proteins: a focus on channels and transporters

After decades of absent or lackluster growth, recent years have at long last witnessed an exponential growth in the number of novel membrane protein structures determined. Every single achievement has had a tremendous impact on the scientific community, providing an unprecedented wealth of information that typically only an atomic resolution structure can contribute to our molecular understanding of how a protein functions. Presented here is a review of some of the most exciting novel structures of channels and transporters determined by X-ray crystallography in the last two years, and a discussion of their analogies, differences and mechanistic implications.

► Slow anion channel 1 and formate transporter FocA have novel gating mechanisms.
► Structures of an anionic Cys-loop receptor and of channelrhodopsin were determined.
► K+ transporter TrkH has intriguing similarities and differences with K+ channels.
► There are novel and interesting folds of primary and secondary active transporters.
► We discuss EIIc of the phosphoenolpyruvate-dependent phosphotransferase system.