Urea transporter
From Proteopedia
Crystal Structure of the Urea Transporter from Desulfovibrio Vulgaris
Publication Abstract from PubMed
Urea is highly concentrated in the mammalian kidney to produce the osmotic gradient necessary for water re-absorption. Free diffusion of urea across cell membranes is slow owing to its high polarity, and specialized urea transporters have evolved to achieve rapid and selective urea permeation. Here we present the 2.3 A structure of a functional urea transporter from the bacterium Desulfovibrio vulgaris. The transporter is a homotrimer, and each subunit contains a continuous membrane-spanning pore formed by the two homologous halves of the protein. The pore contains a constricted selectivity filter that can accommodate several dehydrated urea molecules in single file. Backbone and side-chain oxygen atoms provide continuous coordination of urea as it progresses through the filter, and well-placed alpha-helix dipoles provide further compensation for dehydration energy. These results establish that the urea transporter operates by a channel-like mechanism and reveal the physical and chemical basis of urea selectivity. Crystal structure of a bacterial homologue of the kidney urea transporter., Levin EJ, Quick M, Zhou M, Nature. 2009 Dec 10;462(7274):757-61. Epub . PMID:19865084 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. About this StructureTo help give a better idea of how the urea transporter is oriented in the membrane lipid bilayer, a slab representative of hydrophobic core of the lipid bilayer as calculated by the Orientations of Proteins in Membranes database(University of Michigan, USA) is shown with the red patch of spheres indicating the boundary of the hydrophobic core closet to the outside of the cell and the dark blue patch of spheres indicating the boundary closest to the inside of the cell.
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3D structures of urea transporter or solute carrier family 14
Updated on 13-March-2024
8blp – hUT 1 + cholesterol derivative – human
6qd5 – hUT 1 (mutant) + cholesterol derivative
8blo – hUT 2 + choline derivative
4ezc – bUT + ceramide - bovine
4ezd – bUT + ceramide + selenourea
3k3f, 3me1 – DvUT – Desulfovibrio vulgaris
3m6e – DvUT (mutant)
3k3g – DvUT + dimethylurea
7s6e – UT + urea – synechococcus
Reference for the structure
- Levin EJ, Quick M, Zhou M. Crystal structure of a bacterial homologue of the kidney urea transporter. Nature. 2009 Dec 10;462(7274):757-61. Epub . PMID:19865084 doi:10.1038/nature08558
See Also
- Knepper MA, Mindell JA. Structural biology: Molecular coin slots for urea. Nature. 2009 Dec 10;462(7274):733-4. PMID:20010678 doi:10.1038/462733a
- For Additional Information, See Membrane Channels & Pumps
Reference
Page started with original page on 3k3f seeded by OCA on Thu Jan 28 14:58:46 2010
Proteopedia Page Contributors and Editors (what is this?)
Michal Harel, Wayne Decatur, David Canner, Jaime Prilusky, Joel L. Sussman
Categories: Desulfovibrio vulgaris str. hildenborough | Levin, E J. | NYCOMPS, New York Consortium on Membrane Protein Structure. | Zhou, M. | Channel | Membrane protein | New york consortium on membrane protein structure | Nycomp | Protein structure initiative | Psi-2 | Structural genomic | Transport protein | Transporter | Urea transport | Topic Page