The Atomic Architecture of a Gas Channel

Abstract
Both prokaryotic and eukaryotic cells need to be able to transport ammonia gas. In their Perspective, Knepper and Agre discuss an exciting study ( Khademi et al.) that reports resolution of the crystallographic structure of a bacterial ammonia transport channel, AmtB, to an astonishing 1.35 angstroms, an amazing feat for an integral membrane protein. The structure reveals how ammonia is transported in bacteria and sheds light on how related ammonia transport proteins work in eukaryotic cells.