Monoclonal antibodies targeting two immunodominant epitopes on the Spike protein neutralize emerging SARS-CoV-2 variants of concern.

Background: The emergence of new SARS-CoV-2 variants of concern B.1.1.

X-ray structure of the PHF core C-terminus: insight into the folding of the intrinsically disordered protein tau in Alzheimer's disease.

The major constituent of Alzheimer's disease paired helical filaments (PHF) core is intrinsically disordered protein (IDP) tau. In spite of a considerable effort, insoluble character of PHF together with inherent physical properties of IDP tau have precluded so far reconstruction of PHF 3D structure by X-ray crystallography or NMR spectroscopy. Here we present first crystallographic study of PHF core C-terminus.

Preparation, crystallization and preliminary X-ray analysis of the Fab fragment of monoclonal antibody MN423, revealing the structural aspects of Alzheimer's paired helical filaments.

Monoclonal antibody (mAb) MN423 recognizes Alzheimer's disease specific conformation of tau protein assembled into paired helical filaments (PHF). Since the three-dimensional structure of PHF is currently unavailable, the structure of MN423 binding site could provide important information about PHF conformation with the consequences for the Alzheimer's disease prevention and cure. Fab fragment of MN423 was prepared and purified.

Rapid purification of truncated tau proteins: model approach to purification of functionally active fragments of disordered proteins, implication for neurodegenerative diseases.

Truncated tau is of great interest because of its important role in neurofibrillary pathogenesis in Alzheimer's disease (AD). A major obstacle for characterization of detailed biochemical and biological properties of truncated tau species and their fragments has been the lack of reliable and quick purification methods. Uneven distribution of acidic and basic residues in tau determines that the N- and C-terminal tau fragments require entirely different purification conditions.