Temperature and salt controlled tuning of protein clusters
(2021) In Soft Matter 17(37). p.8506-8516- Abstract
The formation of molecular assemblies in protein solutions is of strong interest both from a fundamental viewpoint and for biomedical applications. While ordered and desired protein assemblies are indispensable for some biological functions, undesired protein condensation can induce serious diseases. As a common cofactor, the presence of salt ions is essential for some biological processes involving proteins, and in aqueous suspensions of proteins can also give rise to complex phase diagrams including homogeneous solutions, large aggregates, and dissolution regimes. Here, we systematically study the cluster formation approaching the phase separation in aqueous solutions of the globular protein BSA as a function of temperature (T), the... (More)
The formation of molecular assemblies in protein solutions is of strong interest both from a fundamental viewpoint and for biomedical applications. While ordered and desired protein assemblies are indispensable for some biological functions, undesired protein condensation can induce serious diseases. As a common cofactor, the presence of salt ions is essential for some biological processes involving proteins, and in aqueous suspensions of proteins can also give rise to complex phase diagrams including homogeneous solutions, large aggregates, and dissolution regimes. Here, we systematically study the cluster formation approaching the phase separation in aqueous solutions of the globular protein BSA as a function of temperature (T), the protein concentration (cp) and the concentrations of the trivalent salts YCl3and LaCl3(cs). As an important complement to structural,i.e.time-averaged, techniques we employ a dynamical technique that can detect clusters even when they are transient on the order of a few nanoseconds. By employing incoherent neutron spectroscopy, we unambiguously determine the short-time self-diffusion of the protein clusters depending oncp,csandT. We determine the cluster size in terms of effective hydrodynamic radii as manifested by the cluster center-of-mass diffusion coefficientsD. For both salts, we find a simple functional formD(cp,cs,T) in the parameter range explored. The calculated inter-particle attraction strength, determined from the microscopic and short-time diffusive properties of the samples, increases with salt concentration and temperature in the regime investigated and can be linked to the macroscopic behavior of the samples.
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- author
- Beck, Christian ; Grimaldo, Marco ; Braun, Michal K. ; Bühl, Lena ; Matsarskaia, Olga ; Jalarvo, Niina H. ; Zhang, Fajun ; Roosen-Runge, Felix LU ; Schreiber, Frank and Seydel, Tilo
- organization
- publishing date
- 2021-10-07
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Soft Matter
- volume
- 17
- issue
- 37
- pages
- 11 pages
- publisher
- Royal Society of Chemistry
- external identifiers
-
- pmid:34490428
- scopus:85116463913
- ISSN
- 1744-683X
- DOI
- 10.1039/d1sm00418b
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © The Royal Society of Chemistry 2021.
- id
- 1624fe2f-7a90-4617-8a15-b19119a1e3ab
- date added to LUP
- 2021-10-22 10:45:23
- date last changed
- 2024-03-23 12:03:21
@article{1624fe2f-7a90-4617-8a15-b19119a1e3ab, abstract = {{<p>The formation of molecular assemblies in protein solutions is of strong interest both from a fundamental viewpoint and for biomedical applications. While ordered and desired protein assemblies are indispensable for some biological functions, undesired protein condensation can induce serious diseases. As a common cofactor, the presence of salt ions is essential for some biological processes involving proteins, and in aqueous suspensions of proteins can also give rise to complex phase diagrams including homogeneous solutions, large aggregates, and dissolution regimes. Here, we systematically study the cluster formation approaching the phase separation in aqueous solutions of the globular protein BSA as a function of temperature (T), the protein concentration (c<sub>p</sub>) and the concentrations of the trivalent salts YCl<sub>3</sub>and LaCl<sub>3</sub>(c<sub>s</sub>). As an important complement to structural,i.e.time-averaged, techniques we employ a dynamical technique that can detect clusters even when they are transient on the order of a few nanoseconds. By employing incoherent neutron spectroscopy, we unambiguously determine the short-time self-diffusion of the protein clusters depending onc<sub>p</sub>,c<sub>s</sub>andT. We determine the cluster size in terms of effective hydrodynamic radii as manifested by the cluster center-of-mass diffusion coefficientsD. For both salts, we find a simple functional formD(c<sub>p</sub>,c<sub>s</sub>,T) in the parameter range explored. The calculated inter-particle attraction strength, determined from the microscopic and short-time diffusive properties of the samples, increases with salt concentration and temperature in the regime investigated and can be linked to the macroscopic behavior of the samples.</p>}}, author = {{Beck, Christian and Grimaldo, Marco and Braun, Michal K. and Bühl, Lena and Matsarskaia, Olga and Jalarvo, Niina H. and Zhang, Fajun and Roosen-Runge, Felix and Schreiber, Frank and Seydel, Tilo}}, issn = {{1744-683X}}, language = {{eng}}, month = {{10}}, number = {{37}}, pages = {{8506--8516}}, publisher = {{Royal Society of Chemistry}}, series = {{Soft Matter}}, title = {{Temperature and salt controlled tuning of protein clusters}}, url = {{http://dx.doi.org/10.1039/d1sm00418b}}, doi = {{10.1039/d1sm00418b}}, volume = {{17}}, year = {{2021}}, }