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  • Effect of protein–protein interactions and solvent viscosity on the rotational diffusion of proteins in crowded environments
Title: Effect of protein–protein interactions and solvent viscosity on the rotational diffusion of proteins in crowded environments
The rotational diffusion of a protein in the presence of protein crowder molecules was analyzed via computer simulations. Cluster formation as a result of transient intermolecular contacts was identified as the dominant effect for reduced rotational diffusion upon crowding. The slow-down in diffusion was primarily correlated with direct protein–protein contacts rather than indirect interactions via shared hydration layers. But increased solvent viscosity due to crowding contributed to a lesser extent. Key protein–protein contacts correlated with a slow-down in diffusion involve largely interactions between charged and polar groups suggesting that the surface composition of a given protein and the resulting propensity for forming interactions with surrounding proteins in a crowded cellular environment may be the major determinant of its diffusive properties.  more » « less
Award ID(s):
1817307
PAR ID:
10096249
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
21
Issue:
2
ISSN:
1463-9076
Page Range / eLocation ID:
876 to 883
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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