Facultad de Ciencias Químicas y Farmacéuticas, Departamento de Bioquímica y Biología Molecular, Universidad de Chile.
Dra. Zahra Alavi, Assistant Professor, Department of Physics, Loyola Marymount University, Los Angeles, California, USA
Martes 5 de abril a las 11.30 hrs.
Formato híbrido
Presencial sala 6, Aulario Facultad de Ciencias Químicas y Farmacéuticas, Dr. Carlos Tobar 964, Independencia, Santiago, Chile (quienes vengan presencial, mostrar afiche y pase de movilidad al ingresar a la facultad)
Coordenadas de zoom aparecerán en las redes de la Facultad, quimica.uchile.cl, www.instagram.com, www.facebook.com o solicitar a Ruth Tapia (rtapia@ciq.uchile.cl)
Idioma: inglés (las preguntas pueden hacerse en castellano, inglés y en farsi)
Resumen:
Microscopic mechanisms of friction, the relation between dissipation and nonlinearity, nonequilibrium processes in nanoscale systems, are all incompletely understood, funda- mental, interconnected problems in nanoscience. These topics appear with experimental immediacy when probing enzyme mechanics by nanorheology. Using the unique capability of measuring directly dissipation occurring in the driven deformation of folded enzyme molecules, this project investigates the origin of this molecular scale friction, specifically the contribution of the surface of the molecule, which includes the hydration layer. Hydration layer dynamics, explored by nanorheology, is also the starting point of a new, dynamic understanding of kosmotropic (order inducing) and chaotropic agents, a physical chemistry topic which this research develops. Finally, the project explores the possibility of light emission from dynamically stressed molecules, with the aim of developing a new spectroscopy to characterize dissipation at the molecular scale. Nano-rheology allows the measurement of the stress–strain relations for a folded, native enzyme with sub-A resolution and at different frequencies. Through recent improvements, the method now allows accurate measurements of the phase of the mechanical response, as well as the amplitude, and thus gives direct access to the dissipation. This project focuses on the dissipative part of the dynamics, which is the nonlinear but reversible mechanical regime of large amplitude deformations for these molecules.
