This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
2abm
From Proteopedia
| Line 1: | Line 1: | ||
| - | [[Image:2abm.gif|left|200px]] | + | [[Image:2abm.gif|left|200px]] |
| - | + | ||
| - | '''Crystal Structure of Aquaporin Z Tetramer Reveals both Open and Closed Water-conducting Channels''' | + | {{Structure |
| + | |PDB= 2abm |SIZE=350|CAPTION= <scene name='initialview01'>2abm</scene>, resolution 3.20Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=BGL:B-2-OCTYLGLUCOSIDE'>BGL</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene>, <scene name='pdbligand=POQ:BIS(((3S,4S,5R,6R)-5-(ETHYL(PHOSPHORYLOXY))-3,4,6-TRIHYDROXY-TETRAHYDRO-2H-PYRAN-2-YL)METHYL)+HYDROGEN+PHOSPHATE'>POQ</scene>, <scene name='pdbligand=PEE:PHOSPHATIDYLETHANOLAMINE'>PEE</scene>, <scene name='pdbligand=3PG:3-PHOSPHOGLYCERIC+ACID'>3PG</scene> and <scene name='pdbligand=AGA:(1S)-2-{[{[(2S)-2,3-DIHYDROXYPROPYL]OXY}(HYDROXY)PHOSPHORYL]OXY}-1-[(PENTANOYLOXY)METHYL]ETHYL OCTANOATE'>AGA</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= aqpZ, bniP ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | ||
| + | }} | ||
| + | |||
| + | '''Crystal Structure of Aquaporin Z Tetramer Reveals both Open and Closed Water-conducting Channels''' | ||
| + | |||
==Overview== | ==Overview== | ||
| Line 7: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
| - | 2ABM is a [ | + | 2ABM is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ABM OCA]. |
==Reference== | ==Reference== | ||
| - | Crystal structure of AqpZ tetramer reveals two distinct Arg-189 conformations associated with water permeation through the narrowest constriction of the water-conducting channel., Jiang J, Daniels BV, Fu D, J Biol Chem. 2006 Jan 6;281(1):454-60. Epub 2005 Oct 20. PMID:[http:// | + | Crystal structure of AqpZ tetramer reveals two distinct Arg-189 conformations associated with water permeation through the narrowest constriction of the water-conducting channel., Jiang J, Daniels BV, Fu D, J Biol Chem. 2006 Jan 6;281(1):454-60. Epub 2005 Oct 20. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/16239219 16239219] |
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| Line 25: | Line 34: | ||
[[Category: membrane protein]] | [[Category: membrane protein]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 15:47:50 2008'' |
Revision as of 13:47, 20 March 2008
| |||||||
| , resolution 3.20Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , , , and | ||||||
| Gene: | aqpZ, bniP (Escherichia coli) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal Structure of Aquaporin Z Tetramer Reveals both Open and Closed Water-conducting Channels
Overview
AqpZ is a homotetramer of four water-conducting channels that facilitate rapid water movements across the plasma membrane of Escherichia coli. Here we report a 3.2 angstroms crystal structure of the tetrameric AqpZ (tAqpZ). All channel-lining residues in the four monomeric channels are found orientated in nearly identical positions with one marked exception at the narrowest channel constriction, where the side chain of a highly conserved Arg-189 adopts two distinct conformational orientations. In one of the four monomers, the guanidino group of Arg-189 points toward the periplasmic vestibule, opening up the constriction to accommodate the binding of a water molecule through a tridentate H-bond. In the other three monomers, the Arg-189 guanidino group bends over to form an H-bond with carbonyl oxygen of the Thr-183, thus occluding the channel. Therefore, the tAqpZ structure reveals two distinct Arg-189 confirmations associated with water permeation through the channel constrictions. Alternation between the two Arg-189 conformations disrupts continuous flow of water, thus regulating the open probability of the water pore. Further, the difference in Arg-189 displacements is correlated with a strong electron density found between the first transmembrane helices of two open channels, suggesting that the observed Arg-189 conformations are stabilized by asymmetrical subunit interactions in tAqpZ.
About this Structure
2ABM is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of AqpZ tetramer reveals two distinct Arg-189 conformations associated with water permeation through the narrowest constriction of the water-conducting channel., Jiang J, Daniels BV, Fu D, J Biol Chem. 2006 Jan 6;281(1):454-60. Epub 2005 Oct 20. PMID:16239219
Page seeded by OCA on Thu Mar 20 15:47:50 2008
Categories: Escherichia coli | Single protein | Daniels, B V. | Fu, D. | Jiang, J. | 3PG | AGA | BGL | PEE | PO4 | POQ | Aquaporin | Membrane protein
