Heterologous expression, purification and characterization of heterodimeric monellin.

摘要: Monellin is an intensely sweet-tasting protein present in the berry of Dioscoreophyllum cumminsii. Naturally occurring monellin (double chain monellin) a heterodimer two subunits commonly referred to as A and B. good model system for structural dynamic studies proteins. Single has been generated by covalently linking naturally double monellin, used extensively folding unfolding studies, well aggregation studies. There are, however, relatively few reports on such with monellin. The primary difficulty associated using appears be lack standard purification method. Here, simple method presented. genes encoding chains were cloned into modified pETDUET vector under separate T7 promoters. expression containing was expressed E. coli BL21 Star (DE3). purified steps chromatography, ion exchange chromatography gel filtration chromatography. This consistently produced 40 mg pure per litre culture, correctly folded native state. purity confirmed mass spectrometry SDS-PAGE analysis. characterized different spectroscopic methods, spectra obtained agreement published