5iws
From Proteopedia
Crystal structure of the transporter MalT, the EIIC domain from the maltose-specific phosphotransferase system
Structural highlights
FunctionQ63GK8_BACCZ The phosphoenolpyruvate-dependent sugar phosphotransferase system (sugar PTS), a major carbohydrate active -transport system, catalyzes the phosphorylation of incoming sugar substrates concomitantly with their translocation across the cell membrane.[SAAS:SAAS00547063] Publication Abstract from PubMedThe phosphoenolpyruvate:carbohydrate phosphotransferase systems are found in bacteria, where they play central roles in sugar uptake and regulation of cellular uptake processes. Little is known about how the membrane-embedded components (EIICs) selectively mediate the passage of carbohydrates across the membrane. Here we report the functional characterization and 2.55-A resolution structure of a maltose transporter, bcMalT, belonging to the glucose superfamily of EIIC transporters. bcMalT crystallized in an outward-facing occluded conformation, in contrast to the structure of another glucose superfamily EIIC, bcChbC, which crystallized in an inward-facing occluded conformation. The structures differ in the position of a structurally conserved substrate-binding domain that is suggested to play a central role in sugar transport. In addition, molecular dynamics simulations suggest a potential pathway for substrate entry from the periplasm into the bcMalT substrate-binding site. These results provide a mechanistic framework for understanding substrate recognition and translocation for the glucose superfamily EIIC transporters. The Structure of a Sugar Transporter of the Glucose EIIC Superfamily Provides Insight into the Elevator Mechanism of Membrane Transport.,McCoy JG, Ren Z, Stanevich V, Lee J, Mitra S, Levin EJ, Poget S, Quick M, Im W, Zhou M Structure. 2016 May 3. pii: S0969-2126(16)30039-9. doi:, 10.1016/j.str.2016.04.003. PMID:27161976[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|