Physico-chemical aspects on molecular motors

Abstract

[eng] The discovery of molecular motors was not a single and isolated event but a set of gradual approaches from microscopic to nanoscopic systems. For example, the knowledge of the activity of muscle cells is pretty old, and even though the first myosin was identified about a century ago, it was not until 1986 when actin filaments were visualized under a microscope. But until 1995 the first single molecule measurement was not performed. Among other technical problems, to deal with such small objects implied thermal noise detection, that couldn’t be distinguished from the desired signal. Microscopic techniques were developed in order to decrease the background noise allowing a progressive improving in image resolution. However, some years before, optical trapping techniques allowed measurement of individual kinesin motion. In this text we will not cover a rigorous survey on the history of single molecule experiments.

[spa] En esta tesis se realiza un estudio teórico de diversos motores moleculares como la kinesina-1, BFM o ARN-polimerosa. La tesis consta de tres partes. La primera es una aproximación al problema de los nanomotores desde un punto de vista de modelos "ratchet". La segunda parte contiene un desarrollo de cinética bioquímica que permite el tratamiento de fuerzas mecánicas en reacciones enzimáticas. Finalmente, la tercera parte es una colección de modelos electrostáticos focalizados en kinesinas. En conjunto, esta tesis es un análisis del funcionamiento de algunos motores moleculares de distintos puntos de vista que se articulan mutuamente. Además, los resultados son normalmente contrastados con los datos experimentales disponibles mostrando un buen acuerdo entre estos y la teoría.