Folding and Stability of Sweet Protein Single-chain Monellin

摘要: Abstract Engineered single-chain monellin (SCM) proteins were constructed by recombinant technology without disrupting the topology and sweet activity of native protein. Data from 8-anilinonaphthalene-1-sulfonic acid fluorescence, size-exclusion chromatography, heteronuclear NMR strongly suggest presence a folding intermediate at 1.5 m GdnHCl for SCM The structural feature data reveals that secondary structures became mostly unstable, protein experiences dynamic equilibrium between unfolded state. All backbone amide protons exchange within 10 min, which imply no stable hydrogen bonds exist in regions intermediate. From unfolding mutagenesis studies, transition midpoints mutant gradually shifted toward lower denaturant concentration, indicating stability reductions proteins. Our results pathways could be regulated combined study spectroscopy mutagenesis, these studies will provide useful information understanding kinetics novel engineered