Abstract Membrane proteins are highly underrepresented in the structural data-base and remain one of the most challenging targets for functional and structural elucidation. Their roles in transport and cellular communication, furthermore, often make over-expression toxic to their host, and their hydrophobicity and structural complexity make isolation and reconstitution a complicated task, especially in cases where proteins are targeted to inclusion bodies. The development of cell-free expression systems provides a very interesting alternative to cell-based systems, since it circumvents many problems such as toxicity or necessity for the transportation of the synthesized protein to the membrane, and constitutes the only system that allows for direct production of membrane proteins in membrane-mimetic environments which may be suitable for liquid state NMR measurements. The unique advantages of the cell-free expression system, including strong expression yields as well as the direct incorporation of almost any combination of amino acids with very little metabolic scrambling, has allowed for the development of a wide-array of isotope labelling techniques which facilitate structural investigations of proteins whose spectral congestion and broad line-widths may have earlier rendered them beyond the scope of NMR. Here we explore various labelling strategies in conjunction with cell-free developments, with a particular focus on α-helical transmembrane proteins which benefit most from such methods.
Content Type Journal Article
Pages 33-43
DOI 10.1007/s10858-009-9364-5
Authors
Solmaz Sobhanifar, Goethe University Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance (BMRZ) Frankfurt/Main Germany
Sina Reckel, Goethe University Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance (BMRZ) Frankfurt/Main Germany
Friederike Junge, Goethe University Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance (BMRZ) Frankfurt/Main Germany
Daniel Schwarz, Goethe University Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance (BMRZ) Frankfurt/Main Germany
Lei Kai, Goethe University Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance (BMRZ) Frankfurt/Main Germany
Mikhail Karbyshev, Goethe University Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance (BMRZ) Frankfurt/Main Germany
Frank Löhr, Goethe University Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance (BMRZ) Frankfurt/Main Germany
Frank Bernhard, Goethe University Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance (BMRZ) Frankfurt/Main Germany
Volker Dötsch, Goethe University Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance (BMRZ) Frankfurt/Main Germany
Suppression of isotope scrambling in cell-free protein synthesis by broadband inhibition of PLP enymes for selective 15N-labelling and production of perdeuterated proteins in H2O
Suppression of isotope scrambling in cell-free protein synthesis by broadband inhibition of PLP enymes for selective 15N-labelling and production of perdeuterated proteins in H2O
Abstract Selectively isotope labelled protein samples can be prepared in vivo or in vitro from selectively labelled amino acids but, in many cases, metabolic conversions between different amino acids result in isotope scrambling. The best results are obtained by cell-free protein synthesis, where metabolic enzymes are generally less active, but isotope scrambling can never be suppressed completely. We show that...
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02-16-2011 09:34 PM
[NMR paper] Cell-free synthesis of 15N-labeled proteins for NMR studies.
Cell-free synthesis of 15N-labeled proteins for NMR studies.
Related Articles Cell-free synthesis of 15N-labeled proteins for NMR studies.
IUBMB Life. 2005 Sep;57(9):615-22
Authors: Ozawa K, Dixon NE, Otting G
Modern cell-free in vitro protein synthesis systems present powerful tools for the synthesis of isotope-labeled proteins in high yields. The production of selectively 15 N-labeled proteins from 15 N-labeled amino acids is particularly economic and yields are often sufficient to analyze the proteins very quickly by two-dimensional NMR...
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12-01-2010 06:56 PM
[NMR paper] Quantitation of protein expression in a cell-free system: Efficient detection of yiel
Quantitation of protein expression in a cell-free system: Efficient detection of yields and 19F NMR to identify folded protein.
Related Articles Quantitation of protein expression in a cell-free system: Efficient detection of yields and 19F NMR to identify folded protein.
J Biomol NMR. 2005 Jan;31(1):11-9
Authors: Neerathilingam M, Greene LH, Colebrooke SA, Campbell ID, Staunton D
We have developed an efficient and novel filter assay method, involving radioactive labelling and imaging, to quantify the expression of soluble proteins from a...
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11-24-2010 11:14 PM
An economical method for producing stable-isotope labeled proteins by the E. coli cel
An economical method for producing stable-isotope labeled proteins by the E. coli cell-free system
Abstract Improvement of the cell-free protein synthesis system (CF) over the past decade have made it one of the most powerful protein production methods. The CF approach is especially useful for stable-isotope (SI) labeling of proteins for NMR analysis. However, it is less popular than expected, partly because the SI-labeled amino acids used for SI labeling by the CF are too expensive. In the present study, we developed a simple and inexpensive method for producing an SI-labeled protein...
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11-07-2010 02:47 PM
[NMR paper] Cell-free synthesis and amino acid-selective stable isotope labeling of proteins for
Cell-free synthesis and amino acid-selective stable isotope labeling of proteins for NMR analysis.
Related Articles Cell-free synthesis and amino acid-selective stable isotope labeling of proteins for NMR analysis.
J Biomol NMR. 1995 Sep;6(2):129-34
Authors: Kigawa T, Muto Y, Yokoyama S
For the application of multidimensional NMR spectroscopy to larger proteins, it would be useful to perform selective labeling of one of the 20 amino acids. For some amino acids, however, amino acid metabolism drastically reduces the efficiency and selectivity...
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08-22-2010 03:50 AM
Cell-free expression and labeling strategies for a new decade in solid-state NMR.
Cell-free expression and labeling strategies for a new decade in solid-state NMR.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles Cell-free expression and labeling strategies for a new decade in solid-state NMR.
N Biotechnol. 2010 Aug 3;
Authors: Abdine A, Verhoeven MA, Warschawski DE
Although solid-state NMR and cell-free expression have recently become standard methods in biology, the combination of the two is still at a very early stage of development. In this...
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08-17-2010 03:36 AM
Cell-free protein synthesis of perdeuterated proteins for NMR studies
Cell-free protein synthesis of perdeuterated proteins for NMR studies
Touraj Etezady-Esfarjani, Sebastian Hiller, Cristina Villalba and Kurt Wüthrich
Journal of Biomolecular NMR; 2007; 39(3); pp 229-238
Abstract:
Cell-free protein synthesis protocols for uniformly deuterated proteins typically yield low, non-uniform deuteration levels. This paper introduces an E. coli cell-extract, D-S30, which enables efficient production of proteins with high deuteration levels for all non-labile hydrogen atom positions. Potential applications of the new protocol may include production of proteins...
Cell-free expression and stable isotope labelling strategies for membrane proteins
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