Reduction of disulfide bonds in an amyloidogenic Bence Jones protein leads to formation of "amyloid-like" fibrils in vitro.
Motivated by the finding that the amino acid sequence of the Bence Jones protein BJP-DIA was identical to that of the main protein component of the amyloid fibrils obtained from the same patient with AL-amyloidosis, (Klafki, H.-W., Kratzin, H.-D., Pick, A.-I., Eckart, K., Karas, M. & Hilschmann, N. (1992) Biochemistry 31, 3265-3272.), we attempted to create "amyloid-like" fibrils from the Bence Jones protein in vitro, without addition of proteolytic enzymes. Reduction of BJP-DIA, solubilized in PBS, pH 7.4, overnight at 37 degrees C resulted in the formation of a precipitate which had affinity for the dye Congo red. Electron microscopy of negatively stained samples of the reduced protein revealed aggregates of linear unbranched fibrils. SDS-polyacrylamide gel electrophoresis demonstrated that the precipitate consisted almost exclusively of intact light chain molecules. This result makes it possible to deduce a molecular model of these amyloid fibrils generated in vitro.
Klafki
H W
HW
Max-Planck-Institute for Experimental Medicine, Göttingen, Germany.
Pick
A I
AI
Pardowitz
I
I
Cole
T
T
Awni
L A
LA
Barnikol
H U
HU
Mayer
F
F
Kratzin
H D
HD
Hilschmann
N
N
D000682:Amyloid / Q000096:biosynthesis*; D001536:Bence Jones Protein / Q000737:chemistry* / Q000302:isolation & purification / Q000648:ultrastructure; D002852:Chromatography, Ion Exchange; D004220:Disulfides / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008854:Microscopy, Electron; D010084:Oxidation-Reduction
D000682:Amyloid; D004220:Disulfides; D001536:Bence Jones Protein