1u7g
From Proteopedia
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| , resolution 1.4Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , and | ||||||
| Gene: | amtB (Escherichia coli) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal Structure of Ammonia Channel AmtB from E. Coli
Overview
The first structure of an ammonia channel from the Amt/MEP/Rh protein superfamily, determined to 1.35 angstrom resolution, shows it to be a channel that spans the membrane 11 times. Two structurally similar halves span the membrane with opposite polarity. Structures with and without ammonia or methyl ammonia show a vestibule that recruits NH4+/NH3, a binding site for NH4+, and a 20 angstrom-long hydrophobic channel that lowers the NH4+ pKa to below 6 and conducts NH3. Favorable interactions for NH3 are seen within the channel and use conserved histidines. Reconstitution of AmtB into vesicles shows that AmtB conducts uncharged NH3.
About this Structure
1U7G is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Mechanism of ammonia transport by Amt/MEP/Rh: structure of AmtB at 1.35 A., Khademi S, O'Connell J 3rd, Remis J, Robles-Colmenares Y, Miercke LJ, Stroud RM, Science. 2004 Sep 10;305(5690):1587-94. PMID:15361618
Page seeded by OCA on Thu Mar 20 14:28:14 2008
