Dr. David Cheung "Conformation of Proteins and Polymers at Soft Interfaces – Insights from Molecular Simulation"

Liquid interfaces, such as the air-water or oil-water interfaces, are attractive templates for the formation of ordered structures. This has been applied to a range of building blocks, both naturally occurring (proteins) or synthetic (polymers, nanoparticles). Structures formed by proteins and polymers are of particular interest as conformational change at interfaces can lead these molecules to adopt structures that are quite different to those in bulk solution. Understanding this requires microscopic knowledge of the molecular conformation; this can be difficult to obtain experimentally but

In this talk I will describe some recent work aimed at understanding the interfacial structure of proteins and polymers and relating this to their behaviour. The conformations adopted by two peptides derived from myoglobin, for which the emulsification behaviour has been studied experimentally [1], will also be discussed. Both peptides adopt similar, compact conformations in bulk solution and readily adsorb onto the air-water interface [2], where they show different interfacial conformations. Similar computational techniques have been used to study the differing interfacial behaviour of lysozyme and alpha-lactalbumin [3]. Using simulations of simple model polymers the relationship between polymer topology and interfacial adsorption has been investigated, with placement of hydrophilic/hydrophobic groups [4] and polymer topology [5] impacting on the polymer adsorption strength. The new insight into the behavior of proteins and polymers at interfaces and surfaces can be used in the design of functional materials.

[1] S. Poon, A. E. Clarke, and C. J. Schultz, J. Coll. Interf. Sci., 213, 193 (1999)
[2] D. L. Cheung, Langmuir, 32, 4405 (2016)
[3] D. L. Cheung, J. Chem. Phys., 147, 195101 (2017)
[4] D. L. Cheung and P. Carbone, Soft Matter, 9, 6841 (2013)
[5] T. Taddese, P. Carbone, and D. L. Cheung, Soft Matter, 11, 81 (2015)
 

invited by Dr. Renate Reiter