Slow Dissolution Kinetics of Model Peptide Fibrils

Abstract

Understanding the kinetics of peptide self-assembly is important because of the involvement of peptide amyloid fibrils in several neurodegenerative diseases. In this paper, we have studied the dissolution kinetics of self-assembled model peptide fibrils after a dilution quench. Due to the low concentrations involved, the experimental method of choice was isothermal titration calorimetry (ITC). We show that the dissolution is a strikingly slow and reaction-limited process, that can be timescale separated from other rapid processes associated with dilution in the ITC experiment. We argue that the rate-limiting step of dissolution involves the breaking up of inter-peptide β–sheet hydrogen bonds, replacing them with peptide–water hydrogen bonds. Complementary pH experiments revealed that the self-assembly involves partial deprotonation of the peptide molecules.

Tensiometric and Thermodynamic Study of Aliphatic and Aromatic Amine in Aqueous D-Glucose Solutions: A Comparative Study

“…A slight increase in the surface tension shows critical aggregation concentration (cac), which governs the nature of the head group/alkyl chain length and counterion of tyramine amino acid [44]. Tyramine behaves like a surfactant, i.e., the surface tension after cac formation decreases linearly with the increase of concentration to a certain point, i.e., CMC, and then nearly constant values are obtained.…”

A guide to studying protein aggregation

“…By fitting experimental data to these mathematical models, the aggregation mechanisms of a protein or a peptide can be unravelled. Here we briefly summarize some of the more popular aggregation mechanisms and the corresponding mathematical models (Table 5), more details can be found in other reviews [194,201,215,216] as well as some more recent publications [217,218]. The equations of these mathematical models can be found in the reference included in Table 5.…”

The Physical Chemistry and Chemical Physics (PCCP) Section of the International Journal of Molecular Sciences in Its Publications: The First 300 Thematic Articles in the First 3 Years

“…Thematic Area 2 includes 22 articles, namely [ 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 ], the typification of which is shown in Table 3 . With some degree of conventionality, it is possible to subdivide the articles published here into two main groups, namely, articles devoted to the study of the kinetics of processes in which any chemical transformations are decisive, and articles devoted to the study of the kinetics of processes in which chemical transformations are either not decisive or absent altogether.…”

“…With some degree of conventionality, it is possible to subdivide the articles published here into two main groups, namely, articles devoted to the study of the kinetics of processes in which any chemical transformations are decisive, and articles devoted to the study of the kinetics of processes in which chemical transformations are either not decisive or absent altogether. Among the articles of the first group, in turn, two categories can be distinguished, in the first of which are the clear majority; the processes related to them were considered in the articles [ 29 , 30 , 31 , 32 , 33 , 35 , 37 , 42 , 43 , 44 , 45 , 46 , 47 ]. For example, in [ 29 ], the kinetics of the aldol condensation of benzaldehyde and heptanal in liquid-phase systems using various solvents was characterized, and a very pronounced effect of the solvent was noted for a given set of identical kinetic parameters (i.e., the same kinetics of the liquid phase can lead to different values of conversion and yield of reaction products depending on the choice of solvent).…”

“…An interesting study was carried out in the article [ 37 ], in which the oxidation of anthracene by hydroxyl radicals obtained by the reaction of 5,10,15,20-tetrakis(4-carboxyphenyl) porphyrin of Fe(III) with hydrogen peroxide under visible radiation in a nitrogen atmosphere was considered. From the list of articles cited above, in our opinion, one should also mention [ 30 , 43 , 45 ], which are remarkable in that, in each of them, the kinetics of any of the biochemical processes was studied (for example, in [ 45 ], the dissolution of self-organizing model peptide fibrils after quenching by dilution using the isothermal titration calorimetry method). Only works [ 34 , 39 , 40 ] are devoted to the study of the kinetics of reactions with the participation of inorganic compounds.…”