Doctoral students seminar (January 14, 2020)

Interaction and aggregation mechanisms of peptides at biologically relevant interfaces

rehearsal by Torsten John

The aggregation of peptides into β-sheet rich oligomers and fibrils is a characteristic phenomenon observed for amyloidogenic peptides. These fibrillation processes have been linked to the onset of ageing-related diseases, such as Alzheimer’s disease or type 2 diabetes. [1] The conditions that cause the aggregation of the soluble peptide monomers into insoluble amyloid plaques is still under investigation. Next to the physicochemical environment, surfaces have been identified to influence the aggregation kinetics. Particularly relevant are nanostructured interfaces due to their high surface-to-volume ratio, and thus large overall surface area. [2]

Nanostructures are abundant in nature in the form of liposomes or synthetic nanoparticles. Both accelerating and inhibiting effects on peptide aggregation into amyloid have been observed, depending on a number of parameters, such as surface coating, nanoparticle size or buffer conditions. [2-4] We have used experimental methods in combination with molecular dynamics (MD) simulations to study the mechanism of peptide aggregation into amyloid at gold nanoparticles. The results on the role of functionalized gold surfaces and citrate-coated gold nanoparticles of varying size are presented. A model that incorporates the competition between peptide-surface attraction and intrinsic aggregation propensity is discussed. [2, 3]

References:
[1] F. Chiti, C. M. Dobson, Annu. Rev. Biochem. 2017, 86, 27-68.
[2] T. John, A. Gladytz, C. Kubeil, L. L. Martin, H. J. Risselada, B. Abel, Nanoscale 2018, 10, 20894-20913.
[3] A. Gladytz, B. Abel, H. J. Risselada, Angew. Chemie – Int. Ed. 2016, 55, 11242-11246.
[4] A. Gladytz, M. Wagner, T. Häupl, C. Elsner, B. Abel, Part. Part. Syst. Charact. 2015, 32, 573-582.

Location: Leipzig University, Linnéstr. 5, SR 215
Time: 3.20pm-5.00pm
Link to OpenStreetMap