Enzyme Activity Regulates Substrate Diffusion by Modulating Viscosity in Crowded Milieu
Bevilacqua, A.; Maciel, M. R.; Sullivan, M. V.; Pascarelli, S.; Dindo, M.; Shen, A. Q.; Laurino, P.
Show abstract
Enzymatic activity and its tight regulation are fundamental to cellular metabolism and life. While classical models of enzyme kinetics explain the behavior of enzymes in dilute buffer solutions, there are elusive properties that emerge from enzymes in their native, crowded environments. In this study, we harness liquid-liquid phase separation (LLPS) to create controlled in vitro droplets that mimic cytosolic protein crowding, offering a unique system to understand enzyme kinetics in complex microenvironments. We uncover a mechanism in which enzyme-induced changes in shear viscosity arise from dynamic interactions among the substrate, product, and the protein crowder. Using fluorescence microscopy, bulk shear rheometry and microrheology, we show that enzymatic activity modifies the apparent viscosity of both protein-rich droplets and the surrounding PEG-rich phase, enhancing substrate mobility and improving substrate access to catalytic sites. Our findings suggest that this enzymatic-viscosity coupling affects substrate availability and influences the organization and dynamics of macromolecular crowding within droplets. These results provide new insights into how enzymes impact both their physical environment and metabolic processes in the cell.
Matching journals
The top 9 journals account for 50% of the predicted probability mass.
Similar papers in this journal
Similar papers in this journal
- High throughput steady-state enzyme kinetics measured in a parallel droplet generation and absorbance detection platform 94%
- Variant-specific interactions at the plasma membrane: Heparan sulfate's impact on SARS-CoV-2 binding kinetics 93%
- Single-Walled Carbon Nanotube Probes for Protease Characterization Directly in Cell-Free Expression Reactions 93%
Similar papers in this journal
Similar papers in this journal
- Manipulation of encapsulated artificial phospholipid membranes using sub-micellar lysolipid concentrations. 96%
- Transient Formation of Supramolecular Complexes Between Hyaluronan and Oligopeptides at Submicromolar Concentration 93%
- Minimized Sample Consumption for Time-Resolved Serial Crystallography Applied to the Redox Cycle of Human NQO1 93%
Similar papers in this journal
- Biomolecular Condensation of Trypsin Prevents Autolysis and Promotes Ca2+-Mediated Activation of Esterase Activity 95%
- Protometabolically generated NADH mediates material properties of aqueous dispersions to coacervate microdroplets 94%
- Applying computational protein design to engineer affibodies for affinity-controlled delivery of vascular endothelial growth factor and platelet-derived growth factor 93%
"Similar papers" are the closest papers from that journal in the model's embedding space. They show what the match is built on, but the ranking comes mostly from a classifier over the whole training set, not from these examples alone.