6KKI

Crystal structure of Drug:Proton Antiporter-1 (DHA1) Family SotB, in the inward-occluded conformation

Summary for 6KKI

• Entry DOI: 10.2210/pdb6kki/pdb
• Descriptor: Sugar efflux transporter, nonyl beta-D-glucopyranoside, 1-methylethyl 1-thio-beta-D-galactopyranoside (3 entities in total)
• Functional Keywords: transporter protein, mfs, protein transport
• Biological source: Escherichia coli (strain K12)
• Total number of polymer chains: 1
• Total formula weight: 46342.08

Authors

Xiao, Q.J.,Deng, D. (deposition date: 2019-07-25, release date: 2020-07-29, Last modification date: 2024-05-29)

Primary citation

Xiao, Q.,Sun, B.,Zhou, Y.,Wang, C.,Guo, L.,He, J.,Deng, D.
Visualizing the nonlinear changes of a drug-proton antiporter from inward-open to occluded state.
Biochem.Biophys.Res.Commun., 534:272-278, 2021

PubMed Abstract: Drug-proton antiporters (DHA) play an important role in multi-drug resistance, utilizing the proton-motive force to drive the expulsion of toxic molecules, including antibiotics and drugs. DHA transporters belong to the major facilitator superfamily (MFS), members of which deliver substrates by utilizing the alternating access model of transport. However, the transport process is still elusive. Here, we report the structures of SotB, a member of DHA1 family (TCDB: 2.A.1.2) from Escherichia coli. Four crystal structures of SotB were captured in different conformations, including substrate-bound occluded, inward-facing, and inward-open states. Comparisons between the four structures reveal nonlinear rigid-body movements of alternating access during the state transition from inward-open to occluded conformation. This work not only reveals the conformational dynamics of SotB but also deepens our understanding of the alternating access mechanism of MFS transporters.

PubMed: 33280821
DOI: 10.1016/j.bbrc.2020.11.096

Experimental method

X-RAY DIFFRACTION (3.064 Å)