Molecular motors are biological molecular machines that are the essential agents
of movement in living organisms. Generally speaking, a motor may be defined
as a device that consumes energy
in one form and converts it into motion or mechanical
work; for example, many protein-based
motors harness the chemical free energy
released by the hydrolysis of ATP in order to perform mechanical work
. In terms of energetic efficiency, these types of motors can be superior to currently available man-made motors.
One important difference between molecular
motors and macroscopic motors is that molecular
motors operate in the thermal bath, an environment where the fluctuations due
to thermal noise are significant.