Single particle analysis of tau oligomer formation induced by metal ions and organic solvents

► Pathological aggregates of tau protein are found in several neurodegenerative diseases. ► Investigation of oligomer formation of tau protein by single-particle fluorescence spectroscopy. ► Formation of distinct tau oligomers is induced by the trivalent metal ions Fe3+ and Al3+ and by organic solvents like DMSO. ► Tau oligomers are relatively stable in solution, dynamic remodeling can be initiated by non-ionic detergents. ► Al3+ induces rapid formation of a different oligomer species of larger size.