Silkworms serve as promising bioreactors for the production of recombinant proteins, including glycoproteins and membrane proteins, for structural and functional protein analyses. However, lack of methodology for stable isotope labeling has been a major deterrent to using this expression system for nuclear magnetic resonance (NMR) structural biology. Here we developed a metabolic isotope labeling technique using commercially available silkworm larvae. The fifth instar larvae were infected with baculoviruses for co-expression of recombinant human immunoglobulin G (IgG) as a test molecule, with calnexin as a chaperone. They were subsequently reared on an artificial diet containing 15N-labeled yeast crude protein extract. We harvested 0.1Â*mg of IgG from larva with a 15N-enrichment ratio of approximately 80Â*%. This allowed us to compare NMR spectral data of the Fc fragment cleaved from the silkworm-produced IgG with those of an authentic Fc glycoprotein derived from mammalian cells. Therefore, we successfully demonstrated that our method enables production of isotopically labeled glycoproteins for NMR studies.
NMR-based stable isotope resolved metabolomics in systems biochemistry
NMR-based stable isotope resolved metabolomics in systems biochemistry
Abstract An important goal of metabolomics is to characterize the changes in metabolic networks in cells or various tissues of an organism in response to external perturbations or pathologies. The profiling of metabolites and their steady state concentrations does not directly provide information regarding the architecture and fluxes through metabolic networks. This requires tracer approaches. NMR is especially powerful as it can be used not only to identify and quantify metabolites in an unfractionated mixture such...
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0
03-03-2011 02:06 AM
Cell-free expression and stable isotope labelling strategies for membrane proteins
Cell-free expression and stable isotope labelling strategies for membrane proteins
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...
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01-09-2011 12:46 PM
Dynamics and interactions of glycoconjugates probed by stable-isotope-assisted NMR spectroscopy.
Dynamics and interactions of glycoconjugates probed by stable-isotope-assisted NMR spectroscopy.
Dynamics and interactions of glycoconjugates probed by stable-isotope-assisted NMR spectroscopy.
Methods Enzymol. 2010;478:305-22
Authors: Yamaguchi Y, Kato K
Unique advantages offered by nuclear magnetic resonance (NMR) spectroscopy provide high-resolution information not only on structures but also on dynamics and interactions of glycoconjugates in solution. These benefits are further enhanced by applying stable-isotope-labeling techniques, which we...
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12-31-2010 07:03 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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Proteins
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11-07-2010 02:47 PM
Stable-isotope-assisted NMR approaches to glycoproteins using immunoglobulin G as a m
Stable-isotope-assisted NMR approaches to glycoproteins using immunoglobulin G as a model system.
Related Articles Stable-isotope-assisted NMR approaches to glycoproteins using immunoglobulin G as a model system.
Prog Nucl Magn Reson Spectrosc. 2010 May;56(4):346-59
Authors: Kato K, Yamaguchi Y, Arata Y
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10-19-2010 04:51 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
Stable-isotope-assisted NMR approaches to glycoproteins using immunoglobulin G as a m
Stable-isotope-assisted NMR approaches to glycoproteins using immunoglobulin G as a model system
Publication year: 2010
Source: Progress in Nuclear Magnetic Resonance Spectroscopy, In Press, Accepted Manuscript, Available online 19 March 2010</br>
Koichi, Kato , Yoshiki, Yamaguchi , Yoji, Arata</br>
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