by Keyword: Beta-peptides
Gul, Merve, Quintana-Romero, Dulce A, Fontana-Escartin, Adrian, Gelmi, Maria Luisa, Perez-Madrigal, Maria M, Chiesa, Enrica, Bucci, Raffaella, Aleman, Carlos, (2025). Electrochemical Response of α/β-peptides: Influence of the Peptide Length, Stereochemistry and Self-Assembly on the Performance of Peptide-Based Electrochemical Sensors Advanced Materials Interfaces 12, e00254 
The electrochemical response of alpha/beta-peptides with (L-Ala-beta-Fpg)n sequence, where beta-Fpg refers to syn 3-amino-2-(2-fluorophenyl)-3-phenylpropanoic acid, has been investigated examining the effects of the peptide length (n = 1-3), the stereochemistry of the beta 2,3-diaryl-amino acid and their self-assembly. alpha/beta-Peptides have been deposited by drop-casting on a conducting polymer (CP) film, which is previously electropolymerized on a stainless steel conducting substrate. The current-potential response of the CP coated by the different studied peptides suggests that, for alpha/beta-peptides, the role played by the electron transport through intermolecular stacking of aromatic side groups prevails over peptide length and stereochemistry. In order to prove such a hypothesis, the experimental conditions used to achieve an ordered self-assembly are optimized for one of the alpha/beta-peptides. The achieved self-assembled structures, which consist of well-defined long microfibers, considerably improve the electrochemical response of the CP. Finally, the prepared alpha/beta-peptide-based electrodes are used to electrochemically detect the oxidation of nicotinamide adenine dinucleotide (NADH). The analytical parameters are better for electrodes with well-defined peptide microfibers than for uncoated CP, corroborating the importance of pi-pi stacking interactions in the response of alpha/beta-peptides.
JTD Keywords: Acid, Alpha/beta-peptides, Beta-peptides, Bioelectronics, Design, Electron-transfer, Foldamers, Nadh, Nadh detection, Nanomaterials, Self-assembly, Stacking interactions
Seuma, M, Faure, AJ, Badia, M, Lehner, B, Bolognesi, B, (2021). The genetic landscape for amyloid beta fibril nucleation accurately discriminates familial Alzheimer's disease mutations Elife 10, e63364
Plaques of the amyloid beta (A beta) peptide are a pathological hallmark of Alzheimer's disease (AD), the most common form of dementia. Mutations in A beta also cause familial forms of AD (fAD). Here, we use deep mutational scanning to quantify the effects of >14,000 mutations on the aggregation of A beta. The resulting genetic landscape reveals mechanistic insights into fibril nucleation, including the importance of charge and gatekeeper residues in the disordered region outside of the amyloid core in preventing nucleation. Strikingly, unlike computational predictors and previous measurements, the empirical nucleation scores accurately identify all known dominant fAD mutations in A beta, genetically validating that the mechanism of nucleation in a cell-based assay is likely to be very similar to the mechanism that causes the human disease. These results provide the first comprehensive atlas of how mutations alter the formation of any amyloid fibril and a resource for the interpretation of genetic variation in A beta.
JTD Keywords: aggregation, kinetics, oligomers, onset, rates, state, Aggregation, Alzheimer disease, Alzheimer's, Amyloid, Amyloid beta-peptides, Computational biology, Deep mutagenesis, Dna mutational analysis, Genetics, Genomics, High-throughput nucleotide sequencing, Kinetics, Mutation, Nucleation, Oligomers, Onset, Plasmids, Precursor protein, Rates, S. cerevisiae, Saccharomyces cerevisiae, State, Systems biology
