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Updated: Dec 24, 2025
09:47
A Microfluidic Technique to Probe Cell Deformability
Published on: September 3, 2014
11.7K
Colloidal stability of the living cell
Håkan Wennerström1, Eloy Vallina Estrada2, Jens Danielsson2
1Division of Physical Chemistry, Department of Chemistry, Lund University, 22100 Lund, Sweden; hakan.wennerstrom@fkem1.lu.se mikael.oliveberg@dbb.su.se.
Summary
Cellular proteins navigate a crowded environment using electrostatic interactions, not just specific binding. This colloidal mechanism explains protein crowding and influences adaptation to extreme conditions.
Area of Science:
- Biophysics
- Cell Biology
- Biochemistry
Background:
- Cellular function is typically viewed through protein-protein interactions and pathways.
- Individual proteins face challenges in partner searching due to a dense environment of non-partners.
- Protein surfaces are often nonconserved, complicating navigation strategies.
Purpose of the Study:
- To investigate the colloidal and electrostatic principles governing intracellular protein searching.
- To demonstrate the fundamental impact of these principles on cellular organization.
- To explain protein crowding and adaptation to extreme environments.
Main Methods:
- Colloidal analysis of cellular systems.
- Examination of naturally occurring proteomes.
- In-cell Nuclear Magnetic Resonance (NMR) data analysis.
Main Results:
- Cellular polyion composition alters electrostatic interactions compared to physiological buffers.
- Protein net-charge density balances attractive forces and surface heterogeneity.
- Nonconserved protein surfaces exhibit chemically biased net-negative repulsion.
- Electrostatic control maintains constant protein crowding via intracellular osmotic pressure.
Conclusions:
- Intracellular protein searching is governed by colloidal electrostatic principles.
- These principles are crucial for cellular organization and protein crowding.
- The study redefines adaptation limits in halophilic organisms based on physicochemical boundaries.
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