Compression of random coils due to macromolecular crowding

Cœur, Clémence Le; Demé, Bruno; Longeville, S.

doi:10.1103/physreve.79.031910

Cited by 46 publications

(53 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…S1). Consistent with the previously reported SANS study of Le Coeur et al [24], Fig. 5(a) shows that for pure PEG and…”

Section: Prl 118 097801 (2017) P H Y S I C a L R E V I E W L E T T Esupporting

confidence: 81%

“…In order to make quantitative the comparisons between simulation and experiment, a useful model system employs PEG as polymeric macromolecule and a polysucrose (Ficoll70) as nanoparticle spherical crowder [24]. For λ ∼ 1 and Φ c ¼ 0.25, the PEG was reported to undergo significant chain compression to 50% of its size in free solution, significantly more than simulations have found [11,12].…”

mentioning

confidence: 99%

“…For λ ∼ 1 and Φ c ¼ 0.25, the PEG was reported to undergo significant chain compression to 50% of its size in free solution, significantly more than simulations have found [11,12]. In these SANS experiments [24], isolated chain behavior was extracted from experiments at finite concentrations (0.004g=cm 3 < c p < 0.03g=cm 3 ) by linear extrapolation to c p ¼ 0. Figure 1 demonstrates why such an experimental extrapolation is problematic.…”

mentioning

confidence: 99%

“…The scaled osmotic pressure (details in the Supplemental Material [26]) obeys a universal behavior as a function of the scaled concentration. In terms of scaled concentrations, the SANS experiments [24] were carried out in the range 0.2 < c scale < 2 in Fig. 1, and are thus completely in the (green hashed) crossover regime.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Combining Diffusion NMR and Small-Angle Neutron Scattering Enables Precise Measurements of Polymer Chain Compression in a Crowded Environment

Palit

Hamilton

et al. 2017

Phys. Rev. Lett.

View full text Add to dashboard Cite

The effect of particles on the behavior of polymers in solution is important in a number of important phenomena such as the effect of "crowding" proteins in cells, colloid-polymer mixtures, and nanoparticle "fillers" in polymer solutions and melts. In this Letter, we study the effect of spherical inert nanoparticles (which we refer to as "crowders") on the diffusion coefficient and radius of gyration of polymers in solution using pulsed-field-gradient NMR and small-angle neutron scattering (SANS), respectively. The diffusion coefficients exhibit a plateau below a characteristic polymer concentration, which we identify as the overlap threshold concentration c ⋆ . Above c ⋆ , in a crossover region between the dilute and semidilute regimes, the (long-time) self-diffusion coefficients are found, universally, to decrease exponentially with polymer concentration at all crowder packing fractions, consistent with a structural basis for the long-time dynamics. The radius of gyration obtained from SANS in the crossover regime changes linearly with an increase in polymer concentration, and must be extrapolated to c ⋆ in order to obtain the radius of gyration of an individual polymer chain. When the polymer radius of gyration and crowder size are comparable, the polymer size is very weakly affected by the presence of crowders, consistent with recent computer simulations. There is significant chain compression, however, when the crowder size is much smaller than the polymer radius gyration.

show abstract

“…S1). Consistent with the previously reported SANS study of Le Coeur et al [24], Fig. 5(a) shows that for pure PEG and…”

Section: Prl 118 097801 (2017) P H Y S I C a L R E V I E W L E T T Esupporting

confidence: 81%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Combining Diffusion NMR and Small-Angle Neutron Scattering Enables Precise Measurements of Polymer Chain Compression in a Crowded Environment

Palit

Hamilton

et al. 2017

Phys. Rev. Lett.

View full text Add to dashboard Cite

show abstract

“…when greater excluded volume of the solution occurred. In agreement with this, random polymer chains undergo significant compaction under conditions of macromolecular crowding (Le Coeur et al 2009). …”

Section: Introductionsupporting

confidence: 51%

The functional roles of the unstructured N- and C-terminal regions in αB-crystallin and other mammalian small heat-shock proteins

Carver

Grosas

Ecroyd

et al. 2017

Cell Stress and Chaperones

View full text Add to dashboard Cite

Small heat-shock proteins (sHsps), such as αB-crystallin, are one of the major classes of molecular chaperone proteins. In vivo, under conditions of cellular stress, sHsps are the principal defence proteins that prevent large-scale protein aggregation. Progress in determining the structure of sHsps has been significant recently, particularly in relation to the conserved, central and β-sheet structured α-crystallin domain (ACD). However, an understanding of the structure and functional roles of the N-and C-terminal flanking regions has proved elusive mainly because of their unstructured and dynamic nature. In this paper, we propose functional roles for both flanking regions, based around three properties: (i) they act in a localised crowding manner to regulate interactions with target proteins during chaperone action, (ii) they protect the ACD from deleterious amyloid fibril formation and (iii) the flexibility of these regions, particularly at the extreme C-terminus in mammalian sHsps, provides solubility for sHsps under chaperone and nonchaperone conditions. In the eye lens, these properties are highly relevant as the crystallin proteins, in particular the two sHsps αA-and αB-crystallin, are present at very high concentrations.

show abstract

Computer Simulations of Single‐Chain Nanoparticles

Moreno

Verso

2017

Single‐Chain Polymer Nanoparticles

View full text Add to dashboard Cite

Compression of random coils due to macromolecular crowding

Cited by 46 publications

References 25 publications

Combining Diffusion NMR and Small-Angle Neutron Scattering Enables Precise Measurements of Polymer Chain Compression in a Crowded Environment

Combining Diffusion NMR and Small-Angle Neutron Scattering Enables Precise Measurements of Polymer Chain Compression in a Crowded Environment

The functional roles of the unstructured N- and C-terminal regions in αB-crystallin and other mammalian small heat-shock proteins

Computer Simulations of Single‐Chain Nanoparticles

Contact Info

Product

Resources

About