Membrane proteins are usually solubilized in polar solvents by incorporation into micelles. Even for small membrane proteins these mixed micelles have rather large molecular masses, typically beyond 50000 Da. The NMR technique TROSY (transverse relaxation-optimized spectroscopy) has been developed for studies of structures of this size in solution. In this paper, strategies for the use of TROSY-based NMR experiments with membrane proteins are discussed and illustrated with results obtained with the Escherichia coli integral membrane proteins OmpX and OmpA in mixed micelles with the detergent dihexanoylphosphatidylcholine (DHPC). For OmpX, complete sequence-specific NMR assignments have been obtained for the polypeptide backbone. The 13C chemical shifts and nuclear Overhauser effect data then resulted in the identification of the regular secondary structure elements of OmpX/DHPC in solution, and in the collection of an input of conformational constraints for the computation of the global fold of the protein. For OmpA, the NMR assignments are so far limited to about 80% of the polypeptide chain, indicating different dynamic properties of the reconstituted OmpA beta-barrel from those of OmpX. Overall, the present data demonstrate that relaxation-optimized NMR techniques open novel avenues for studies of structure, function and dynamics of integral membrane proteins.
NMR structures of polytopic integral membrane proteins.
NMR structures of polytopic integral membrane proteins.
NMR structures of polytopic integral membrane proteins.
Mol Membr Biol. 2011 Aug 2;
Authors: Patching SG
Abstract Membrane proteins represent up to 30% of the proteins in all organisms, they are involved in many biological processes and are the molecular targets for around 50% of validated drugs. Despite this, membrane proteins represent less than 1% of all high-resolution protein structures due to various challenges associated with applying the main biophysical techniques used for...
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08-04-2011 11:41 AM
Solution NMR studies of polytopic ?-helical membrane proteins.
Solution NMR studies of polytopic ?-helical membrane proteins.
Solution NMR studies of polytopic ?-helical membrane proteins.
Curr Opin Struct Biol. 2011 Jul 18;
Authors: Nietlispach D, Gautier A
NMR spectroscopy has established itself as one of the main techniques for the structural study of integral membrane proteins. Remarkably, over the last few years, substantial progress has been achieved in the structure determination of increasingly complex polytopical ?-helical membrane proteins, with their size approaching ~100kDa. Such advances are the...
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07-23-2011 08:54 AM
Solution NMR study of integral membrane proteins.
Solution NMR study of integral membrane proteins.
Solution NMR study of integral membrane proteins.
Curr Opin Chem Biol. 2011 Jun 18;
Authors: Kang C, Li Q
Signals between a cell and its environment are often transmitted through membrane proteins; therefore, many membrane proteins, including G protein-coupled receptors (GPCRs) and ion channels, are important drug targets. Structural information about membrane proteins remains limited owing to challenges in protein expression, purification and the selection of membrane-mimicking systems that will...
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06-21-2011 01:50 PM
[NMR paper] How to prepare membrane proteins for solid-state NMR: A case study on the alpha-helical integral membrane protein diacylglycerol kinase from E. coli.
How to prepare membrane proteins for solid-state NMR: A case study on the alpha-helical integral membrane protein diacylglycerol kinase from E. coli.
Related Articles How to prepare membrane proteins for solid-state NMR: A case study on the alpha-helical integral membrane protein diacylglycerol kinase from E. coli.
Chembiochem. 2005 Sep;6(9):1693-700
Authors: Lorch M, Faham S, Kaiser C, Weber I, Mason AJ, Bowie JU, Glaubitz C
Several studies have demonstrated that it is viable to use microcrystalline preparations of water-soluble proteins as...
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12-01-2010 06:56 PM
[NMR paper] Solution structure and dynamics of integral membrane proteins by NMR: a case study in
Solution structure and dynamics of integral membrane proteins by NMR: a case study involving the enzyme PagP.
Related Articles Solution structure and dynamics of integral membrane proteins by NMR: a case study involving the enzyme PagP.
Methods Enzymol. 2005;394:335-50
Authors: Hwang PM, Kay LE
Solution NMR spectroscopy is rapidly becoming an important technique for the study of membrane protein structure and dynamics. NMR experiments on large perdeuterated proteins typically exploit the favorable relaxation properties of backbone amide...
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11-24-2010 11:14 PM
[NMR paper] Solid-state NMR spectroscopic studies of an integral membrane protein inserted into a
Solid-state NMR spectroscopic studies of an integral membrane protein inserted into aligned phospholipid bilayer nanotube arrays.
Related Articles Solid-state NMR spectroscopic studies of an integral membrane protein inserted into aligned phospholipid bilayer nanotube arrays.
J Am Chem Soc. 2004 Aug 11;126(31):9504-5
Authors: Lorigan GA, Dave PC, Tiburu EK, Damodaran K, Abu-Baker S, Karp ES, Gibbons WJ, Minto RE
This communication demonstrates for the first time that solid-state NMR spectroscopic studies can be used to investigate aligned...
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11-24-2010 10:01 PM
[NMR paper] NMR structure of the integral membrane protein OmpX.
NMR structure of the integral membrane protein OmpX.
Related Articles NMR structure of the integral membrane protein OmpX.
J Mol Biol. 2004 Mar 5;336(5):1211-21
Authors: Fernández C, Hilty C, Wider G, Güntert P, Wüthrich K
The structure of the integral membrane protein OmpX from Escherichia coli reconstituted in 60 kDa DHPC micelles (OmpX/DHPC) was calculated from 526 NOE upper limit distance constraints. The structure determination was based on complete sequence-specific assignments for the amide protons and the Val, Leu, and Ile(delta1)...
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11-24-2010 09:25 PM
[NMR paper] On choosing a detergent for solution NMR studies of membrane proteins.
On choosing a detergent for solution NMR studies of membrane proteins.
Related Articles On choosing a detergent for solution NMR studies of membrane proteins.
J Biomol NMR. 1998 May;11(4):381-6
Authors: Vinogradova O, Sönnichsen F, Sanders CR
Translational diffusion coefficients and catalytic activities were measured for the integral membrane protein diacylglycerol kinase (DAGK) in a variety of types of detergent micelles. Despite the structural diversity of the detergents examined, the translational diffusion coefficients observed for DAGK...
Solution NMR studies of the integral membrane proteins OmpX and OmpA from Escherichia
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