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Dynamic Properties of Motor Proteins with Two Subunits

Anatoly B. Kolomeisky·Hubert Phillips III
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Abstract

The dynamics of motor protein molecules that have two subunits is investigated using simple discrete stochastic models. Exact steady-state analytical expressions are obtained for velocities and dispersions for any number of intermediate states and conformations between the corresponding binding states of proteins. These models enabled a detailed description and comparison of two possible mechanisms of the motion of motor proteins along the linear tracks: the hand-over-hand mechanism when the motion of subunits alternate, and the inchworm mechanism when one subunit is always trailing another one. It is shown that particles in the hand-over-hand mechanism move faster and fluctuate more than the molecules in the inchworm mechanism. The effect of external forces on dynamic properties of motor proteins is discussed. Finally, a method is proposed for distinguishing between these two mechanisms based on experimental observations.

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Anatoly B. Kolomeisky, Hubert Phillips III. 2005-03-08. Dynamic Properties of Motor Proteins with Two Subunits. https://doi.org/10.1088/0953-8984%2F17%2F47%2F017

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