Alpha Synuclein A90C Mutant Monomers

Thioflavin-T (ThT) fluorescence remains a common measurement of alpha-synuclein fibril formation, yet ThT exhibits poor affinity for oligomers and early aggregates. The alpha-synuclein A90C mutant monomers can be specifically labelled with alternative fluorophores (such as Alexa 488/Alexa 647) via maleimide chemistry to enable more sensitive FRET analysis of aggregation. The A90C mutant showed no perturbation of monomer structure and Alexa Fluor dye attachment to cysteine 90 was demonstrated to have no effect on the kinetics of fibril formation (1-3). Residue 90 is at the periphery of the NAC region, a key constituent of the alpha-synuclein β-sheet fibril core, which results in fluorophores on different monomers coming into close proximity upon formation of β-sheet structure during aggregation (4). Note - to prevent the potential mis-translation of alpha-synuclein Y136 as C136 during E.coli expression, the Y136-TAT construct was used (5).

SNCA, alpha-synuclein, synuclein, Alpha synuclein monomer, Alpha-synuclein monomer, Alpha synuclein protein monomer, Alpha synuclein monomer, Alpha-synuclein protein, SNCA protein

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