Folding-unfolding of immunoglobulin domains in titin: a simple two-state model.
The folding-unfolding reaction rate process in the giant protein titin is studied within a simple two-state model. The molecule is assumed to be stretched by an external force which modulates the potential barrier associated with the folded state. A two-state model for this process is assumed (i.e., the immunoglobulin domains are considered to be either folded or unfolded, with no intermediate states at all). Simple calculations yield a relation between the force and the pulling speed that agrees fairly well with data from experiments and Monte Carlo simulations performed recently. Moreover, in a regime involving ultrafast pulling, the results show that the detailed form of the potential barrier is irrelevant, a conclusion that agrees with the current theoretical work on molecular dynamics.
Marín
J L
JL
Centro de Investigación en Física, Universidad de Sonora, Mexico.
Muñiz
J
J
Huerta
M
M
Trujillo
X
X
D000595:Amino Acid Sequence; D002151:Calorimetry; D064211:Connectin; D007136:Immunoglobulins / Q000737:chemistry*; D008565:Membrane Proteins / Q000737:chemistry; D008956:Models, Chemical; D009010:Monte Carlo Method; D009124:Muscle Proteins / Q000737:chemistry*; D011489:Protein Denaturation; D017510:Protein Folding; D011494:Protein Kinases / Q000737:chemistry*; D017433:Protein Structure, Secondary; D013816:Thermodynamics
D064211:Connectin; D007136:Immunoglobulins; D008565:Membrane Proteins; D009124:Muscle Proteins; D011494:Protein Kinases