Abstract:
:Elucidating the mechanism of folding of polynucleotides depends on accurate estimates of free energy surfaces and a quantitative description of the kinetics of structure formation. Here, the kinetics of hairpin formation in single-stranded DNA are measured after a laser temperature jump. The kinetics are modeled as configurational diffusion on a free energy surface obtained from a statistical mechanical description of equilibrium melting profiles. The effective diffusion coefficient is found to be strongly temperature-dependent in the nucleation step as a result of formation of misfolded loops that do not lead to subsequent zipping. This simple system exhibits many of the features predicted from theoretical studies of protein folding, including a funnel-like energy surface with many folding pathways, trapping in misfolded conformations, and non-Arrhenius folding rates.
journal_name
Proc Natl Acad Sci U S Aauthors
Ansari A,Kuznetsov SV,Shen Ydoi
10.1073/pnas.131477798keywords:
subject
Has Abstractpub_date
2001-07-03 00:00:00pages
7771-6issue
14eissn
0027-8424issn
1091-6490pii
98/14/7771journal_volume
98pub_type
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