title: Polymer surface properties control the function of heavy meromyosin in dynamic nanodevices.
abstract: The actin-myosin system, responsible for muscle contraction, is also the force-generating element in dynamic nanodevices operating with surface-immobilized motor proteins. These devices require materials that are amenable to micro- and nano-fabrication, but also preserve the bioactivity of molecular motors. The complexity of the protein-surface systems is greatly amplified by those of the polymer-fluid interface; and of the structure and function of molecular motors, making the study of these interactions critical to the success of molecular motor-based nanodevices. We measured the density of the adsorbed motor protein (heavy meromyosin, HMM) using quartz crystal microbalance; and motor bioactivity with ATPase assay, on a set of model surfaces, i.e., nitrocellulose, polystyrene, poly(methyl methacrylate), and poly(butyl methacrylate), poly(tert-butyl methacrylate). A higher hydrophobicity of the adsorbing material translates in a higher total number of HMM molecules per unit area, but also in a lower uptake of water, and a lower ratio of active per total HMM molecules per unit area. We also measured the motility characteristics of actin filaments on the model surfaces, i.e., velocity, smoothness and deflection of movement, determined via in vitro motility assays. The filament velocities were found to be controlled by the relative number of active HMM per total motors, rather than their absolute surface density. The study allowed the formulation of the general engineering principles for the selection of polymeric materials for the manufacturing of dynamic nanodevices using protein molecular motors.
authors: Industrial Research Institute Swinburne, Swinburne University of Technology, Hawthorn, Victoria, 3122 Australia.
authors: Kristi L
authors: KL
authors: Hanson
authors: Department of Electrical Engineering and Electronics, The University of Liverpool, Liverpool, L693GJ United Kingdom.
authors: Florin
authors: F
authors: Fulga
authors: Department of Electrical Engineering and Electronics, The University of Liverpool, Liverpool, L693GJ United Kingdom.
authors: Serban
authors: S
authors: Dobroiu
authors: Industrial Research Institute Swinburne, Swinburne University of Technology, Hawthorn, Victoria, 3122 Australia.
authors: Gerardin
authors: G
authors: Solana
authors: Department of Bioengineering, McGill University, Montreal, Quebec, H3A0C3 Canada.
authors: Ondrej
authors: O
authors: Kaspar
authors: Department of Bioengineering, McGill University, Montreal, Quebec, H3A0C3 Canada.
authors: Viola
authors: V
authors: Tokarova
authors: Industrial Research Institute Swinburne, Swinburne University of Technology, Hawthorn, Victoria, 3122 Australia; Department of Electrical Engineering and Electronics, The University of Liverpool, Liverpool, L693GJ United Kingdom; Department of Bioengineering, McGill University, Montreal, Quebec, H3A0C3 Canada. Electronic address: dan.nicolau@mcgill.ca.
authors: Dan V
authors: DV
authors: Nicolau
mesh_terms: D008841:Actin Cytoskeleton / Q000737:chemistry / Q000502:physiology; D015374:Biosensing Techniques; D015879:Myosin Subfragments / Q000737:chemistry* / Q000502:physiology; D009218:Myosins / Q000737:chemistry / Q000502:physiology; D036103:Nanotechnology; D011108:Polymers / Q000737:chemistry; D058525:Quartz Crystal Microbalance Techniques; D013499:Surface Properties
chemical_list: D015879:Myosin Subfragments; D011108:Polymers; D009218:Myosins
keywords: Molecular motors; Nanodevices; Protein adsorption