5D0Y

Substrate bound S-component of folate ECF transporter

Summary for 5D0Y

• Entry DOI: 10.2210/pdb5d0y/pdb
• Descriptor: Conserved hypothetical membrane protein, FOLIC ACID (2 entities in total)
• Functional Keywords: ecf transporter, folate, s-component, membrane protein, vitamin, transport protein
• Biological source: Lactobacillus delbrueckii subsp. bulgaricus
• Total number of polymer chains: 2
• Total formula weight: 41921.87

Authors

Swier, L.J.Y.M.,Guskov, A.,Slotboom, D.J. (deposition date: 2015-08-03, release date: 2016-04-06, Last modification date: 2024-01-10)

Primary citation

Swier, L.J.,Guskov, A.,Slotboom, D.J.
Structural insight in the toppling mechanism of an energy-coupling factor transporter.
Nat Commun, 7:11072-11072, 2016

PubMed Abstract: Energy-coupling factor (ECF) transporters mediate uptake of micronutrients in prokaryotes. The transporters consist of an S-component that binds the transported substrate and an ECF module (EcfAA'T) that binds and hydrolyses ATP. The mechanism of transport is poorly understood but presumably involves an unusual step in which the membrane-embedded S-component topples over to carry the substrate across the membrane. In many ECF transporters, the S-component dissociates from the ECF module after transport. Subsequently, substrate-bound S-components out-compete the empty proteins for re-binding to the ECF module in a new round of transport. Here we present crystal structures of the folate-specific transporter ECF-FolT from Lactobacillus delbrueckii. Interaction of the ECF module with FolT stabilizes the toppled state, and simultaneously destroys the high-affinity folate-binding site, allowing substrate release into the cytosol. We hypothesize that differences in the kinetics of toppling can explain how substrate-loaded FolT out-competes apo-FolT for association with the ECF module.

PubMed: 27026363
DOI: 10.1038/ncomms11072

Experimental method

X-RAY DIFFRACTION (3.014 Å)