title: Time-dependent motor properties of multipedal molecular spiders.
abstract: Molecular spiders are synthetic biomolecular walkers that use the asymmetry resulting from cleavage of their tracks to bias the direction of their stepping motion. Using Monte Carlo simulations that implement the Gillespie algorithm, we investigate the dependence of the biased motion of molecular spiders, along with binding time and processivity, on tunable experimental parameters, such as number of legs, span between the legs, and unbinding rate of a leg from a substrate site. We find that an increase in the number of legs increases the spiders' processivity and binding time but not their mean velocity. However, we can increase the mean velocity of spiders with simultaneous tuning of the span and the unbinding rate of a spider leg from a substrate site. To study the efficiency of molecular spiders, we introduce a time-dependent expression for the thermodynamic efficiency of a molecular motor, allowing us to account for the behavior of spider populations as a function of time. Based on this definition, we find that spiders exhibit transient motor function over time scales of many hours and have a maximum efficiency on the order of 1%, weak compared to other types of molecular motors.
authors: Department of Physics, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, V5A 1S6, Canada.
authors: Laleh
authors: L
authors: Samii
authors: Gerhard A
authors: GA
authors: Blab
authors: Elizabeth H C
authors: EH
authors: Bromley
authors: Heiner
authors: H
authors: Linke
authors: Paul M G
authors: PM
authors: Curmi
authors: Martin J
authors: MJ
authors: Zuckermann
authors: Nancy R
authors: NR
authors: Forde
mesh_terms: D003198:Computer Simulation; D008956:Models, Chemical; D008958:Models, Molecular; D020409:Molecular Motor Proteins / Q000737:chemistry* / Q000648:ultrastructure*; D009038:Motion; D011487:Protein Conformation
chemical_list: D020409:Molecular Motor Proteins