Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/9416
Share/Impact:
Título : Dynamics of one-state downhill protein folding
Autor : Peng, Li, Oliva, Fabiana Y., Naganathan, Athi N., Muñoz van den Eynde, Víctor
Palabras clave : Downhill folding
Folding landscape
Landscape topography
Protein dynamics
Biophysics
Fecha de publicación : 31-Dec-2008
Editor: National Academy of Sciences (U.S.)
Citación : Proc. Natl. Acad. Sci. USA, DOI 10.1073/pnas.0802986106
Resumen: The small helical protein BBL has been shown to fold and unfold in the absence of a free energy barrier according to a battery of quantitative criteria in equilibrium experiments, including probe-dependent equilibrium unfolding, complex coupling between denaturing agents, characteristic DSC thermogram, gradual melting of secondary structure, and heterogeneous atom-by-atom unfolding behaviors spanning the entire unfolding process. Here, we present the results of nanosecond T-jump experiments probing backbone structure by IR and end-to-end distance by FRET. The folding dynamics observed with these two probes are both exponential with common relaxation times but have large differences in amplitude following their probe-dependent equilibrium unfolding. The quantitative analysis of amplitude and relaxation time data for both probes shows that BBL folding dynamics are fully consistent with the one-state folding scenario and incompatible with alternative models involving one or several barrier crossing events. At 333 K, the relaxation time for BBL is 1.3 μs, in agreement with previous folding speed limit estimates. However, late folding events at room temperature are an order of magnitude slower (20 μs), indicating a relatively rough underlying energy landscape. Our results in BBL expose the dynamic features of one-state folding and chart the intrinsic time-scales for conformational motions along the folding process. Interestingly, the simple self-averaging folding dynamics of BBL are the exact dynamic properties required in molecular rheostats, thus supporting a biological role for one-state folding.
Descripción : Supporting information (12 pages) available at: http://www.pnas.org/content/suppl/2008/12/31/0802986106.DCSupplemental/0802986106SI.pdf
Published online before print December 31, 2008.
Versión del editor: http://dx.doi.org/10.1073/pnas.0802986106
URI : http://hdl.handle.net/10261/9416
ISSN: 0027-8424
DOI: 10.1073/pnas.0802986106
Appears in Collections:(CIB) Artículos

Files in This Item:
There are no files associated with this item.
Show full item record
 
CSIC SFX LinksSFX Query


Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.