Colloquium

Molecular Motors: Observations and Theory

Michael E. Fisher
Institute for Physical Science and Technology
University of Maryland
Friday, May 4, 2007
Higgins 310, 3 pm

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 microtubule, while consuming one ‘fuel molecule’ of ATP per step, and may reach an average speed of nearly a micron per second.

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 environments, and subsequent developments, yield effective tools.