Institute for Physical
Science and Technology
and Department of Physics University of Maryland
MOTORS: Observations and Theory
Michael E. Fisher
Professor and Regents Professor
Wolf prize winner and member of
the American Academy of Arts and Sciences
Abstract: Molecular motors are
protein molecules that drive much active biological motion .
Recently, striking experiments have observed single motor protein
molecules in vitro pulling loads along linear molecular tracks.
Thus a kinesin molecule takes hundreds of discrete steps of 8.2
nm along a mirotubule, while consuming one "fuel molecule" of
ATP per step, and may reach an average speed of nearly a micron per
How "mechanical" are such , motors? And what forces do they exert? How
"should" their motion be described theoretically? Exact
results derived for random walks in random enviroments, and subsequent
developments, yiels effective tools.