Biphysics

This is a study of types of causative present events in a molecular motor, which are proteins - such as myosin, kinesina and dynein - present inside the cells and associated with, among other functions, the transport of substances along microtubules rails ( Spudich, 2006). Molecular motors are essential for the whole body movement and play an important role in brain. It is known that their malfunction is associated with Alzheimer's disease (Stokin & Goldstein, 2006), and it is reasonable to assume that they are at the base of the deliberative processes of decision making.
Adopt a general perspective that can be characterized as a "methodological reductionism", to try to reduce the macroscopic causality recognized in biology the most basic causal events. A causal event is defined by the possibility of an intervention or manipulation. In a previous study, we identified three types of causal events in quantum systems (less than 0.1 nm) interacting with macroscopic measuring devices (Person, 2013).
In this study, we set aside the quantum scale and up to three orders of magnitude study the causal processes in macromolecules 50nm, immersed in an aqueous solution of the cell medium and described by classical physical chemistry. On this scale, the molecules receive the shock of a huge number of water molecules per second, which makes them around, rotating, vibrating and twisting stochastically in Brownian motion, with power of 10-8 watts order. The macromolecule relates to microtubule (in the case of kinesina and dynein) by means of two "feet", and detaches when one occurs hydrolysis of ATP molecule, a process whose full power for a macromolecule is only 10-16 watts. Even with extremely low power to the Brownian motion, the hydrolysis of ATP is essential for unidirectional movement of the protein. The molecular motor floating end along the microtubule towards the core or the core in the opposite direction. On average, however, dynein has a net shift towards the core (electrically more negative) and kinesina in the opposite direction (more positive charge). Understanding the mechanism involved is the result of research of the past 25 years, and will be presented briefly (Astumian, 2010).
Identify at least four types of causal events are present at the molecular motor movement.
(1) The Brownian motion of the macromolecule can be reduced to a set of individual collisions with water molecules, which provides power to the molecule explore the area available to it, the viscous medium. This is random mechanical causes.
(2) The molecular motor is attached to the microtubule by electrostatic attraction, with a key-lock type fitting. Such a fitting can be regarded as a causal event. If one foot is loose, it stochastically explore all its accessible region can be fixed in microtubule tens of nanometers more forward.
(3) To be able action molecular engine, it is essential frequent conversion of ATP molecule present in the aqueous solution to ADP + P, a hydrolysis process which occurs stochastically. In this chemical reaction, the release of a quantum of energy occurs, which leads to a change in the conformation of the protein molecules and release of a foot.
(4) To explain the existence of molecular motors and the efficient exercise of its biological function of transport and movement, one must take into account root causes associated with natural selection. There is actually a whole family of evolutionary lineages of molecular motors.