This book provides a molecular view of membrane transport by means of
numerous biochemical and biophysical techniques. The rapidly growing
numbers of atomic structures of transporters in different conformations
and the constant progress in bioinformatics have recently added deeper
insights. The unifying mechanism of energized solute transport across
membranes is assumed to consist of the conformational cycling of a
carrier protein to provide access to substrate binding sites from either
side of a cellular membrane. Due to the central role of active membrane
transport there is considerable interest in deciphering the principles
of one of the most fundamental processes in nature: the alternating
access mechanism. This book brings together particularly significant
structure-function studies on a variety of carrier systems from
different transporter families: Glutamate symporters, LeuT-like fold
transporters, MFS transporters and SMR (RND) exporters, as well as
ABC-type importers. The selected examples impressively demonstrate how
the combination of functional analysis, crystallography, investigation
of dynamics and computational studies has made it possible to create a
conclusive picture or more precisely, "a molecular movie". Although we
are still far from a complete molecular description of the alternating
access mechanism, remarkable progress has been made from static
snapshots towards membrane transport dynamics.