Multidomain proteins under force

Valle-Orero, Jessica; Rivas-Pardo, Jaime Andres; Popa, Ionel


Advancements in single-molecule force spectroscopy techniques such as atomic force microscopy and magnetic tweezers allow investigation of how domain folding under force can play a physiological role. Combining these techniques with protein engineering and HaloTag covalent attachment, we investigate similarities and differences between four model proteins: I10 and I91-two immunoglobulin-like domains from the muscle protein titin, and two a. alpha + beta fold proteins-ubiquitin and protein L. These proteins show a different mechanical response and have unique extensions under force. Remarkably, when normalized to their contour length, the size of the unfolding and refolding steps as a function of force reduces to a single master curve. This curve can be described using standard models of polymer elasticity, explaining the entropic nature of the measured steps. We further validate our measurements with a simple energy landscape model, which combines protein folding with polymer physics and accounts for the complex nature of tandem domains under force. This model can become a useful tool to help in deciphering the complexity of multidomain proteins operating under force.

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Título según WOS: ID WOS:000398392700002 Not found in local WOS DB
Título de la Revista: NANOTECHNOLOGY
Volumen: 28
Número: 17
Fecha de publicación: 2017


Notas: ISI