Stretching Single Domain Proteins: Phase Diagram and Kinetics of Force-Induced Unfolding
arXiv:cond-mat/9905355 · doi:10.1073/pnas.96.11.6166
Abstract
Single molecule force spectroscopy reveals unfolding of domains in titin upon stretching. We provide a theoretical framework for these experiments by computing the phase diagrams for force-induced unfolding of single domain proteins using lattice models. The results show that two-state folders (at zero force) unravel cooperatively whereas stretching of non-two-state folders occurs through intermediates. The stretching rates of individual molecules show great variations reflecting the heterogeneity of force-induced unfolding pathways. The approach to the stretched state occurs in a step-wise "quantized" manner. Unfolding dynamics depends sensitively on topology. The unfolding rates increase exponentially with force f till an optimum value which is determined by the barrier to unfolding when f=0. A mapping of these results to proteins shows qualitative agreement with force-induced unfolding of Ig-like domains in titin. We show that single molecule force spectroscopy can be used to map the folding free energy landscape of proteins in the absence of denaturants.
12 pages, Latex, 6 ps figures
References in corpus (1)
Cited by in corpus (26)
- Single-molecule experiments in biological physics: methods and applications
- Mechanical unfolding of RNA hairpins
- Small-world networks and the conformation space of a lattice polymer chain
- Non-conservative forces and effective temperatures in active polymers
- Force Dependent Hopping Rates of RNA Hairpins can be Estimated from Accurate Measurement of the Folding Landscapes
- Stretching of a polymer below the Theta point
- Force-dependent switch in protein unfolding pathways and transition state movements
- Propensity to form amyloid fibrils is encoded as excitations in the free energy landscape of monomeric proteins
- Refolding dynamics of stretched biopolymers upon force quench
- Refolding upon force quench and pathways of mechanical and thermal unfolding of ubiquitin
- Molten globule-like transition state of protein barnase measured with calorimetric force spectroscopy
- Theory of biopolymer stretching at high forces
- Force induced conformational transition in a system of interacting stiff polymer: Application to unfolding
- Reversible stretching of homopolymers and random heteropolymers
- Mapping the energy landscape of biomolecules using single molecule force correlation spectroscopy (FCS): Theory and applications
- Infinite Switch Simulated Tempering in Force (FISST)
- Mechanical response of random heteropolymers
- Force-induced unfolding of a homopolymer on fractal lattice: exact results vs. mean field predictions
- Single Chain Force Spectroscopy: Sequence Dependence
- Extracting Structural Information of a Heteropolymer from Force-Extension Curves
- The 3-dimensional random walk with applications to overstretched DNA and the protein titin
- Exact solution of the Zwanzig-Lauritzen model of Polymer Crystallization under Tension
- Three Bead Rotating Chain model shows universality in the stretching of proteins
- Unstructured intermediate states in single protein force experiments
- Theoretical Perspectives on Protein Folding
- Role of Resultant Dipole Moment in Mechanical Dissociation of Biological Complexes