The statistical thermodynamics of stretched multi-stranded biomolecules

• Main Author: Tailor, H.
• Published: University College London (University of London) 2013
• Subjects: 500
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.626287

Mechanical experiments on single polymers have provided force-displacement data for a number of species, including multi-stranded polymers such as DNA and collagen. The interpretation of this information at the mesoscale requires the use of statistical mechanics to calculate the free energies of various structures. In this thesis, we look initially at the behaviour of a single stranded polymer in extension and go on to consider two particular multi-stranded polymers, DNA and collagen, both of which have di erent but similar tertiary structures. In simplifying the multistranded structures evaluate the partition function by a transfer matrix approach in one dimension. The numerical solution of the equations provide the restoring force as a function of the extension of a single strand, as well as a description of the molecular distortion that is induced. In DNA we investigate molecular breakage schemes for base-pair potentials that simulate the severing of bonds when a single strand is pulled, and the tearing of one strand from another in triple-stranded collagen.