<p>Bacterial high affinity transport systems are involved in active transport of solutes across the cytoplasmic membrane. The protein components of these traffic systems include one or two transmembrane protein components, one or two membrane-associated ATP-binding proteins and a high affinity periplasmic solute-binding protein. In Gram-positive bacteria, which are surrounded by a single membrane and therefore have no periplasmic region, the equivalent proteins are bound to the membrane via an N-terminal lipid anchor. These homologue proteins do not play an integral role in the transport process per se, but probably serve as receptors to trigger or initiate translocation of the solute through the membrane by binding to external sites of the integral membrane proteins of the efflux system. In addition at least some solute-binding proteins function in the initiation of sensory transduction pathways.</p><p>Maltodextrin binding protein (MBP) is the primary component of bacterialhigh-affinity active transport and chemotaxis [<cite idref="PUB00003346"/>]. It is a monomericprotein, with 2 globular domains separated by a 2- or 3-stranded hinge.MBP binds and transports linear oligosaccharides (of up to 7 glucosylunits), as well as 2 cyclic maltodextrins which, although bindingtightly, cannot be transported nor initiate a chemotactic response [<cite idref="PUB00000375"/>].It is thought that the hinge region is critical for the correct functioning of MBP, not just in the binding and recognition of sugars,but also in allowing and maintaining the integrity of initiation ofboth active transport and chemotaxis [<cite idref="PUB00007931"/>]. </p> Maltose binding protein