Skirtingų purtymo sąlygų poveikis pelės prioninio baltymo MoPrP 89-230 agregacijai / ; Effect of different agitation conditions on the aggregation of the mouse prion protein moprp 89-230.

Amyloidogenic peptides and proteins property to convert from their native functional states into fibrillar amyloid aggregates is associated with neurodegenerative disorders, such as prionopathies. Amyloid proteins tend to be polymorphic and environmental factors (temperature, agitation, pH, protein concentration and etc.) have a significant influence on the experimental results. Since there are countless studies employing different intensities of sample agitation, this environmental factor requires additional investigation. The aim of this bachelor’s work is to determine how different agitation intensities affect the aggregation kinetics of a mouse prion protein fragment (MoPrP 89-230) and the secondary structure of the resulting amyloid fibrils. MoPrP 89-230 was purified using immobilized nickel ion affinity chromatography. Protein samples were incubated under three agitation conditions (200, 400, and 600 rotations per minute (RPM)). The kinetics of aggregation and fibrils stability under denaturing conditions were determined by recording the fluorescence intensity of the Thioflavin-T. The secondary structure of fibrils was determined by analyzing each sample’s Fourier-transform infrared spectroscopy spectra. It was observed that agitation intensities did not alter lag time of aggregation, however rates of fibrillar elongation appears to be significantly different with the lowest rate at 200 RPM and highest rate at 400 RPM. A diverse collection of secondary structures (at least four structure types) were observed in all three cases. All of them exhibit different stability under denaturing conditions and morphology. It was observed that subgroup variability decrease with increasing agitation intensities.