Crystal‐Liquid Phase Transitions

Aberrant protein folding underpins many neurodegenerative diseases as well as certain myopathies and cancers. Protein misfolding can be driven by the presence of distinctive prion and prion-like regions within certain proteins. These prion and prion-like regions have also been found to drive liquid-liquid phase separation. Liquid-liquid phase separation is thought to be an important physiological process, but one that is prone to malfunction. Thus, aberrant liquid-to-solid phase transitions may drive protein aggregation and fibrillization, which could give rise to pathological inclusions. Here, we review prions and prion-like proteins, their roles in phase separation and disease, as well as potential therapeutic approaches to counter aberrant phase transitions.

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From the bulk to clusters: Solid-liquid phase transitions and precursor effects

Phase Transitions ◽

10.1080/01411599008210235 ◽

1990 ◽

Vol 24-26 (1) ◽

pp. 283-342 ◽

Cited By ~ 35

Author(s):

R. Kofman ◽

P. Cheyssac ◽

R. Garrigos

Keyword(s):

Phase Transitions ◽

Liquid Phase ◽

Precursor Effects ◽

Solid Liquid

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Water and its anomalies in perspective: tetrahedral liquids with and without liquid–liquid phase transitions

Physical Chemistry Chemical Physics ◽

10.1039/b000206m ◽

2000 ◽

Vol 2 (8) ◽

pp. 1559-1566 ◽

Cited By ~ 189

Author(s):

C. A. Angell ◽

R. D. Bressel ◽

M. Hemmati ◽

E. J. Sare ◽

J. C. Tucker

Keyword(s):

Phase Transitions ◽

Liquid Phase

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Evolution of weak cooperative interactions for biological specificity

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1815912115 ◽

2018 ◽

Vol 115 (47) ◽

pp. E11053-E11060 ◽

Cited By ~ 11

Author(s):

Ang Gao ◽

Krishna Shrinivas ◽

Paul Lepeudry ◽

Hiroshi I. Suzuki ◽

Phillip A. Sharp ◽

...

Keyword(s):

Phase Transitions ◽

Liquid Phase ◽

Evolutionary Model ◽

Cross Reactivity ◽

Cellular Functions ◽

Cooperative Interactions ◽

Lethal Mutations ◽

Evolutionary Changes ◽

Biological Specificity ◽

Multicellular Organisms

A hallmark of biological systems is that particular functions and outcomes are realized in specific contexts, such as when particular signals are received. One mechanism for mediating specificity is described by Fisher’s “lock and key” metaphor, exemplified by enzymes that bind selectively to a particular substrate via specific finely tuned interactions. Another mechanism, more prevalent in multicellular organisms, relies on multivalent weak cooperative interactions. Its importance has recently been illustrated by the recognition that liquid-liquid phase transitions underlie the formation of membraneless condensates that perform specific cellular functions. Based on computer simulations of an evolutionary model, we report that the latter mechanism likely became evolutionarily prominent when a large number of tasks had to be performed specifically for organisms to function properly. We find that the emergence of weak cooperative interactions for mediating specificity results in organisms that can evolve to accomplish new tasks with fewer, and likely less lethal, mutations. We argue that this makes the system more capable of undergoing evolutionary changes robustly, and thus this mechanism has been repeatedly positively selected in increasingly complex organisms. Specificity mediated by weak cooperative interactions results in some useful cross-reactivity for related tasks, but at the same time increases susceptibility to misregulation that might lead to pathologies.

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Viscosity Measurement of Olive Oil under Pressure

Food Science & Nutrition Technology ◽

10.23880/fsnt-16000275 ◽

2021 ◽

Vol 6 (5) ◽

Author(s):

Pawlicki LT

Keyword(s):

Phase Transition ◽

High Pressure ◽

Phase Transitions ◽

Liquid Phase ◽

Olive Oil ◽

Measurement Method ◽

Viscosity Measurement ◽

Food Preservation ◽

Characteristic Frequencies ◽

Viscosity Changes

This article presents changes in the viscosity of olive oil during compression. The test was carried out indirectly by measuring the dependence of the resonance frequency of the piezoelectric immersed in olive oil on pressure. For this purpose, for successive pressures, the resonance curves were read and the values of the characteristic frequencies were determined. Viscosity changes were analysed and related to the compression and crystallization taking place in the tested substance. During this research, a phase transition from the liquid phase to the alpha crystalline phase was detected, during which the resonant frequency of the tested piezoelectric reached a minimum and the viscosity related to this frequency reached a maximum. The measurement method developed in this paper can be used to detect the phase transitions of oils subjected to pressure. This may find application in the oil production and high-pressure food preservation industries for which this knowledge is essential for the safe and trouble-free use of their machines.

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Liquid-liquid phase separation and morphology of internally mixed dicarboxylic acids/ammonium sulfate/water particles

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-11-29141-2011 ◽

2011 ◽

Vol 11 (10) ◽

pp. 29141-29194 ◽

Cited By ~ 4

Author(s):

M. Song ◽

C. Marcolli ◽

U. K. Krieger ◽

A. Zuend ◽

T. Peter

Keyword(s):

Phase Transitions ◽

Phase Separation ◽

Liquid Phase ◽

Ammonium Sulfate ◽

Particle Surface ◽

Dicarboxylic Acids ◽

Liquid Phase Separation ◽

Model Systems ◽

Second Phase ◽

Liquid Liquid Phase Separation

Abstract. Knowledge of the physical state and morphology of internally mixed organic/inorganic aerosol particles is still largely uncertain. To obtain more detailed information on liquid-liquid phase separation (LLPS) and morphology of the particles, we investigated complex mixtures of atmospherically relevant dicarboxylic acids containing 5–7 carbon atoms (C5, C6 and C7) having oxygen-to-carbon atomic ratios (O:C) of 0.80, 0.67, and 0.57, respectively, mixed with ammonium sulfate (AS). With micrometer-sized particles of C5/AS/H2O, C6/AS/H2O and C7/AS/H2O as model systems deposited on a hydrophobically coated substrate, laboratory experiments were conducted for various organic-to-inorganic dry mass ratios (OIR) using optical microscopy and Raman spectroscopy. When exposed to cycles of relative humidity (RH), each system showed significantly different phase transitions. While the C5/AS/H2O particles showed no LLPS with OIR = 2:1, 1:1 and 1:4 down to 20% RH, the C6/AS/H2O and C7/AS/H2O particles exhibit LLPS upon drying at RH 50% to 85% and ~90%, respectively, via spinodal decomposition, growth of a second phase from the particle surface or nucleation-and-growth mechanisms depending on the OIR. This suggests that LLPS commonly occurs within the range of O:C<0.7 in tropospheric organic-inorganic aerosols. To support the comparison and interpretation of the experimentally observed phase transitions, thermodynamic equilibrium calculations were performed with the AIOMFAC model. For the C7/AS/H2O and C6/AS/H2O systems, the calculated phase diagrams agree well with the observations while for the C5/AS/H2O system LLPS is predicted by the model at RH below 60% and higher AS concentration, but was not observed in the experiments. Both core-shell structures and partially engulfed structures were observed for the investigated particles, suggesting that such morphologies might also exist in tropospheric aerosols.

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Simple Calculation of Phase Diagrams for Liquid-Liquid Phase Transitions in Solutions of Two Macromolecular Solute Species

Biophysical Journal ◽

10.1016/j.bpj.2019.11.2683 ◽

2020 ◽

Vol 118 (3) ◽

pp. 484a

Author(s):

Allen P. Minton

Keyword(s):

Phase Transitions ◽

Liquid Phase ◽

Phase Diagrams ◽

Simple Calculation ◽

Solute Species

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Supramolecular Fuzziness of Intracellular Liquid Droplets: Liquid–Liquid Phase Transitions, Membrane-Less Organelles, and Intrinsic Disorder

Molecules ◽

10.3390/molecules24183265 ◽

2019 ◽

Vol 24 (18) ◽

pp. 3265 ◽

Cited By ~ 12

Author(s):

Vladimir N. Uversky

Keyword(s):

Phase Transitions ◽

Liquid Phase ◽

Intrinsically Disordered Proteins ◽

Intrinsically Disordered Protein ◽

Disordered Proteins ◽

Bacterial Cells ◽

Liquid Droplets ◽

Intrinsically Disordered ◽

Wide Range ◽

Characteristic Features

Cells are inhomogeneously crowded, possessing a wide range of intracellular liquid droplets abundantly present in the cytoplasm of eukaryotic and bacterial cells, in the mitochondrial matrix and nucleoplasm of eukaryotes, and in the chloroplast’s stroma of plant cells. These proteinaceous membrane-less organelles (PMLOs) not only represent a natural method of intracellular compartmentalization, which is crucial for successful execution of various biological functions, but also serve as important means for the processing of local information and rapid response to the fluctuations in environmental conditions. Since PMLOs, being complex macromolecular assemblages, possess many characteristic features of liquids, they represent highly dynamic (or fuzzy) protein–protein and/or protein–nucleic acid complexes. The biogenesis of PMLOs is controlled by specific intrinsically disordered proteins (IDPs) and hybrid proteins with ordered domains and intrinsically disordered protein regions (IDPRs), which, due to their highly dynamic structures and ability to facilitate multivalent interactions, serve as indispensable drivers of the biological liquid–liquid phase transitions (LLPTs) giving rise to PMLOs. In this article, the importance of the disorder-based supramolecular fuzziness for LLPTs and PMLO biogenesis is discussed.

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