L-Arginine reduces thioflavin T fluorescence but not fibrillation of bovine serum albumin.
This work examines the effects of L-arginine (L-Arg) on the aggregation and amyloid fibrillation of bovine serum albumin (BSA). We demonstrate that L-Arg dose-dependently reduces thioflavin T (ThT) fluorescence of BSA within the L-Arg concentration range used (0-1.4 M). However, as revealed by electron microscopy, size exclusion chromatography, and dynamic light scattering results, L-Arg does not prevent amyloid-like fibril formation by BSA. We conclude that L-Arg competes against ThT for binding sites on BSA amyloid-like fibrils, leading to biased results in ThT fluorescence measurements. Moreover, the use of ThT fluorescence assay to screen for potential inhibitors against amyloid fibrillation can give misleading results.
Liu
Kuan-Nan
KN
Department of Chemical Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan.
Wang
Hsiang-Yun
HY
Chen
Chih-Yuan
CY
Wang
Steven S-S
SS
D000818:Animals; D001120:Arginine / Q000737:chemistry*; D052160:Benzothiazoles; D001665:Binding Sites; D002417:Cattle; D005453:Fluorescence; D046529:Microscopy, Electron, Transmission; D011485:Protein Binding; D011487:Protein Conformation; D012710:Serum Albumin, Bovine / Q000737:chemistry* / Q000648:ultrastructure; D013844:Thiazoles / Q000737:chemistry*
D052160:Benzothiazoles; D013844:Thiazoles; C009462:thioflavin T; D012710:Serum Albumin, Bovine; D001120:Arginine