5XLS

Crystal structure of UraA in occluded conformation

Summary for 5XLS

• Entry DOI: 10.2210/pdb5xls/pdb
• Descriptor: Uracil permease, URACIL, 12-TUNGSTOPHOSPHATE, ... (4 entities in total)
• Functional Keywords: occluded conformation, dimer, transport protein
• Biological source: Escherichia coli O157:H7
• Cellular location: Cell inner membrane ; Multi- pass membrane protein : P0AGM8
• Total number of polymer chains: 1
• Total formula weight: 51812.87

Authors

Yu, X.Z.,Yang, G.H.,Yan, C.Y.,Yan, N. (deposition date: 2017-05-11, release date: 2017-07-05, Last modification date: 2023-11-22)

Primary citation

Yu, X.,Yang, G.,Yan, C.,Baylon, J.L.,Jiang, J.,Fan, H.,Lu, G.,Hasegawa, K.,Okumura, H.,Wang, T.,Tajkhorshid, E.,Li, S.,Yan, N.
Dimeric structure of the uracil:proton symporter UraA provides mechanistic insights into the SLC4/23/26 transporters
Cell Res., 27:1020-1033, 2017

PubMed Abstract: The Escherichia coli uracil:proton symporter UraA is a prototypical member of the nucleobase/ascorbate transporter (NAT) or nucleobase/cation symporter 2 (NCS2) family, which corresponds to the human solute carrier family SLC23. UraA consists of 14 transmembrane segments (TMs) that are organized into two distinct domains, the core domain and the gate domain, a structural fold that is also shared by the SLC4 and SLC26 transporters. Here we present the crystal structure of UraA bound to uracil in an occluded state at 2.5 Å resolution. Structural comparison with the previously reported inward-open UraA reveals pronounced relative motions between the core domain and the gate domain as well as intra-domain rearrangement of the gate domain. The occluded UraA forms a dimer in the structure wherein the gate domains are sandwiched by two core domains. In vitro and in vivo biochemical characterizations show that UraA is at equilibrium between dimer and monomer in all tested detergent micelles, while dimer formation is necessary for the transport activity. Structural comparison between the dimeric UraA and the recently reported inward-facing dimeric UapA provides important insight into the transport mechanism of SLC23 transporters.

PubMed: 28621327
DOI: 10.1038/cr.2017.83

Experimental method

X-RAY DIFFRACTION (2.5 Å)