Macromolecule Content

• Total Structure Weight: 2886.42 
• Atom Count: 206 
• Residue Count: 28 
• Unique protein chains: 1

2KBV

Structural and functional analysis of TM XI of the NHE1 isoform of thE NA+/H+ exchanger

• DOI: 10.2210/pdb2KBV/pdb
• BMRB: 16056

• Classification: MEMBRANE PROTEIN
• Organism(s): Homo sapiens


• Deposited: 2008-12-09 Released: 2009-01-27 
• Deposition Author(s): Lee, B.L., Li, X., Liu, Y., Sykes, B.D., Fliegel, L.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 50 
• Conformers Submitted: 40 
• Selection Criteria: structures with the lowest energy 

Literature

Structural and Functional Analysis of Transmembrane XI of the NHE1 Isoform of the Na+/H+ Exchanger

Lee, B.L., Li, X., Liu, Y., Sykes, B.D., Fliegel, L.

(2009) J.Biol.Chem. 284: 11546-11556

• PubMed: 19176522 
• DOI: 10.1074/jbc.M809201200


• PubMed Abstract: 
  

The Na(+)/H(+) exchanger isoform 1 is a ubiquitously expressed integral membrane protein that regulates intracellular pH in mammals by extruding an intracellular H(+) in exchange for one extracellular Na(+). We characterized structural and functional aspects of the critical transmembrane (TM) segment XI (residues 449-470) by using cysteine scanning mutagenesis and high resolution NMR. Each residue of TM XI was mutated to cysteine in the background of the cysteine-less protein and the sensitivity to water-soluble sulfhydryl reactive compounds MTSET ((2-(trimethylammonium) ethyl)methanethiosulfonate) and MTSES ((2-sulfonatoethyl) methanethiosulfonate) was determined for those residues with at least moderate activity remaining. Of the residues tested, only proteins with mutations L457C, I461C, and L465C were inhibited by MTSET. The activity of the L465C mutant was almost completely eliminated, whereas that of the L457C and I461C mutants was partially affected. The structure of a peptide representing TM XI (residues Lys(447)-Lys(472)) was determined using high resolution NMR spectroscopy in dodecylphosphocholine micelles. The structure consisted of helical regions between Asp(447)-Tyr(454) and Phe(460)-Lys(471) at the N and C termini of the peptide, respectively, connected by a region with poorly defined, irregular structure consisting of residues Gly(455)-Gly(459). TM XI of NHE1 had a structural similarity to TM XI of the Escherichia coli Na(+)/H(+) exchanger NhaA. The results suggest that TM XI is a discontinuous helix, with residue Leu(465) contributing to the pore.

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Organizational Affiliation: 

Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Sodium/hydrogen exchanger 1	A	28	Homo sapiens	Mutation(s): 0  Gene Names: SLC9A1 (APNH1, NHE1)
Find proteins for P19634 (Homo sapiens) Go to Gene View: SLC9A1 Go to UniProtKB:  P19634

Small Molecules

Modified Residues  2 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
NH2	A	NON-POLYMER	H2 N		--
ACE	A	NON-POLYMER	C2 H4 O		--

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 50 
• Conformers Submitted: 40 
• Selection Criteria: structures with the lowest energy 
• Olderado: 2KBV Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2008-12-09 
• Released Date: 2009-01-27 
• Deposition Author(s): Lee, B.L., Li, X., Liu, Y., Sykes, B.D., Fliegel, L.

Revision History 

• Version 1.0: 2009-01-27
  Type: Initial release
• Version 1.1: 2011-07-13
  Type: Version format compliance