Conformational biosensor for diagnosis of prion diseases.
A fluorescence technology to monitor the proliferation of amyloidogenic neurological disorders is proposed. A crude brain homogenate (0.01%) from animals infected with a transmissible spongiform encephalopathy is employed as a catalytic medium initiating conformational changes in 520 nM polypeptide biosensors (Tris/trifluoroethanol 50% mixture at pH 7). The fluorescence methods utilize pyrene residues covalently attached to the peptide ends. The coil-to-beta-strand transitions in biosensor molecules cause elevation of a distinct fluorescence band of the pyrene aggregates (i.e. excimers). This approach enables the detection of infectious prion proteins at fmol, does not require antibody binding or protease treatment. Technology might be adopted for diagnosing a large variety of conformational disorders as well as for generic high-throughput screening of the amyloidogenic potential in plasma.
Department of Biochemistry and Molecular Biology, Georgetown University School of Medicine, Washington, DC 20057, USA. ovt@georgetown.edu
Olga
O
Tcherkasskaya
Eugene A
EA
Davidson
Mary Jo
MJ
Schmerr
Cindy S
CS
Orser
D000682:Amyloid / Q000737:chemistry; D000818:Animals; D015374:Biosensing Techniques; D001709:Biotechnology / Q000379:methods*; D001921:Brain / Q000378:metabolism; D002942:Circular Dichroism; D006224:Cricetinae; D003670:Deer; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D006863:Hydrogen-Ion Concentration; D009422:Nervous System Diseases / Q000378:metabolism; D010455:Peptides / Q000737:chemistry; D017096:Prion Diseases / Q000378:metabolism* / Q000473:pathology; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D012756:Sheep; D013050:Spectrometry, Fluorescence; D014466:Ultraviolet Rays
D000682:Amyloid; D010455:Peptides; D004121:Dimethyl Sulfoxide