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PubMed · 15063772

An efficient system for small protein expression and refolding.

Yuan Cheng·Dinshaw J Patel
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Abstract

The low expression yield and poor refolding efficiency of small recombinant proteins expressed in Escherichia coli have continued to hinder the large-scale purification of such proteins for structural and biological investigations. A system based on a small fusion partner, the B1 domain of Streptococcal protein G (GB1), was utilized to overcome this problem. We have tested this system on a small cysteine-rich toxin, mutant myotoxin alpha (MyoP20G). The highly expressed fusion protein was refolded using an unfolding/refolding protocol. Due to the small size of GB1, we were able to monitor the unfolding/refolding status by heteronuclear single quantum coherence (HSQC) NMR spectroscopy. The final product yielded well-resolved NMR spectra, with a topology corresponding to the natural product. We conclude that GB1 not only increases the expression level but also enhances the refolding of small proteins.

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Bacterial ProteinsCrotalid VenomsEscherichia coliFeasibility StudiesGene Expression Regulation, BacterialGene Transfer TechniquesGenetic EnhancementMagnetic Resonance SpectroscopyMolecular WeightProtein EngineeringProtein FoldingRecombinant Fusion ProteinsEvaluation StudyJournal Article

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Yuan Cheng, Dinshaw J Patel. 2004-04-30. An efficient system for small protein expression and refolding.. https://doi.org/10.1016/j.bbrc.2004.03.068

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