Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9816848 | Ultramicroscopy | 2005 | 6 Pages |
Abstract
We investigated the mechanical unfolding of single circularly permuted green fluorescent protein (cpGFP) with atomic force microscopy (AFM). The molecule was stretched from its N- and C-termini by an external force causing an elongation of the polypeptide chain up to its full length. The features of the force-extension (F-E) curves were found to depend on the stretching speed. At fast speeds, we detected one peak in the F-E curves before final rupture of the extended molecule, which we interpreted as the unfolding of two terminal halves within cpGFP. We observed several more force peaks in a sawtooth pattern at much slower speeds, and explained the appearance of such force peaks as cooperative unfolding of the hidden sub-structures inside each terminal half.
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Physical Sciences and Engineering
Materials Science
Nanotechnology
Authors
Tong Wang, Ken Nakajima, Atsushi Miyawaki, Masahiko Hara,