Direct observation of multiple and stochastic transition states by a feedback-controlled single-molecule force measurement.
To overcome the ensemble-averaging barrier, single-molecule experiments have been performed, but energy landscapes comprising multiple intermediates have not yet been defined. We performed mechanical unfolding of staphylococcal nuclease using intermolecular force microscopy, modified AFM with high resolution and feedback control of the positioning. The force dropped vertically just after its peak, and multiple transition states were detected as force peaks. The multiple and stochastic intermediates found in the present study provide new important information on protein folding.
Fukagawa
Akihiro
A
Structural Biology Center, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.
Hiroshima
Michioa
M
Sakane
Isao
I
Tokunaga
Makio
M
D008836:Micrococcal Nuclease / Q000737:chemistry*; D018625:Microscopy, Atomic Force / Q000295:instrumentation / Q000379:methods*; D017510:Protein Folding
D008836:Micrococcal Nuclease