78 / 79
Engineering Approaches to Biomolecular Motors: From in vitro to in vivo Poster Abstracts
73
34-POS
Board 34
Transform Ation of a Protein Nano-walker into a Nano-motor by Feedback
Martin J. Zuckermann
1
, Regina Schmitt
4
, Nancy R. Forde
1
, , Elizabeth H. Bromley
3
, Heiner
Linke
4
, Christopher N. Angstmann
5
, Paul M. Curmi
2
.
1
Simon Fraser University, Burnaby, BC, Canada,
2
University of New South Wales, Sydney, New
South Wales, Australia,
3
University of Durham, Durham, United Kingdom,
4
Lund University,
Lund, Sweden,
5
University of New South Wales, Sydney, Australia.
Biological protein nano-motors are vital to the survival and function of cells. The objective of
our research is to design synthetic protein motors which mimic such biological nano-motors. To
this purpose we have conceived a concept for a protein nano-walker dubbed Synthetic Kinesin
Inspired Protein (SKIP), so called because it is inspired by kinesin’s use of restricted diffusional
search for forward head binding. The SKIP model is composed of coiled coils and ligand-gated
repressor proteins; its two types of repressors each bind to specific sequences patterned
symmetrically along a linear double-stranded DNA track. SKIP is designed to undergo biased
directional motion along this track in the presence of a temporally symmetric ligand pulse
sequence. Thus, in this design directionality is achieved by persistence rather than asymmetry.
Furthermore its symmetry allows it to reverse through the influence of a sufficient rearward force
or the use of specific track termini.
Here, we explore the role of feedback in enhancing SKIP’s performance. First, we alter the
direction of the applied force, in order to maximize the work being done by SKIP as it walks
(Zuckermann et al., New J. Phys. 2015). In an alternative approach, we alter the duration of
ligand pulses, switching to a new potential binding state as soon as forward motion is detected.
In this scheme we can maximize output power. We evaluate the information cost and benefits of
feedback in these two scenarios. The properties of this new construct demonstrate that SKIP can
indeed be engineered by feedback to become a directional and processive nano-motor.