Single molecule observation on the folding process of proteins

To understand the mechanism of protein folding, in which the conformational heterogeneity of the unfolded protein is reduced drastically in a single kinetic step,investigations at the single molecule level are necessary. The single molecule fluorescence spectroscopy is one of the methods that have been applied to protein folding. The structure and dynamics of the unfolded state of proteins were revealed. In addition, the upper limit of the transition path time, the time required for the transition from the unfolded state to the folded state, was estimated to be 30 (is. The future prospect of the single molecule method in protein folding study is briefly discussed in this report.