Search results for " Concanavalin A"

Phasor-FLIM analysis of Thioflavin T self-quenching in Concanavalin amyloid fibrils

2020

The formation of amyloid structures has traditionally been related to human neurodegenerative pathologies and, in recent years, the interest in these highly stable nanostructures was extended to biomaterial sciences. A common method to monitor amyloid growth is the analysis of Thioflavin T fluorescence. The use of this highly selective dye, diffused worldwide, allows mechanistic studies of supramolecular assemblies also giving back important insight on the structure of these aggregates. Here we present experimental evidence of self-quenching effect of Thioflavin T in presence of amyloid fibrils. A significant reduction of fluorescence lifetime of this dye which is not related to the propert…

Unlocked Concanavalin A Forms Amyloid-like Fibrils from Coagulation of Long-lived "Crinkled'' Intermediates

2013

Understanding the early events during amyloid aggregation processes is crucial to single out the involved molecular mechanisms and for designing ad hoc strategies to prevent and reverse amyloidogenic disorders. Here, we show that, in conditions in which the protein is positively charged and its conformational flexibility is enhanced, Concanavalin A leads to fibril formation via a non-conventional aggregation pathway. Using a combination of light scattering, circular dichroism, small angle X-ray scattering, intrinsic (Tryptophan) and extrinsic (ANS) fluorescence and confocal and 2-photon fluorescence microscopy we characterize the aggregation process as a function of the temperature. We high…

Amyloid Fibrils Formation in Concanavalin A studied by Dynamic Light Scattering and Fluorescence techniques

2007

Amyloid Fibrils Formation of Concanavalin A at Basic pH

2011

Mechanisms of partial unfolding and aggregation of proteins are of extreme interest in view of the fact that several human pathologies are characterized by the formation and deposition of protein-insoluble material, mainly composed of amyloid fibrils. Here we report on an experimental study on the heat-induced aggregation mechanisms, at basic pH, of concanavalin A (ConA), used as a model system. Thioflavin T (ThT) fluorescence and multiangle light scattering allowed us to detect different intertwined steps in the formation of ConA aggregates. In particular, the ThT fluorescence increase, observed in the first phase of aggregation, reveals the formation of intermolecular β-sheet structure wh…

THz spectroscopy study of amyloid fibrils

2013

In suitable conditions proteins can modify their native conformation and associate to form aggregates with different morphologies in dependence on the external physico-chemical conditions. This phenomenon, one of the most challenging in life sciences, is associated with widely diffused pathologies such as Alzheimer’s, Parkinson’s and Creutzfeldt-Jacob’s diseases. Of particular relevance are ordered elongated aggregates with highly organized patterns of hydrogen-bonds, known as amyloid fibrils. While much biological and structural information are available about amyloids, and in spite of the fundamental paradigm of structure-dynamics-function relation in proteins, much less is known about th…

Insights into amyloid fibrils dynamics from neutron scattering

2011

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