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Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
Published on: January 16, 2016
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Understanding enzyme behavior in a crowded scenario through modulation in activity, conformation and dynamics
Harshita Rastogi1, Pramit K Chowdhury1
1Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
Biochimica Et Biophysica Acta. Proteins and Proteomics
|July 23, 2021
Summary
Macromolecular crowding affects enzyme activity. Researchers studied adenylate kinase AK3L1 in the presence of common crowders, finding that while most enhanced activity, Ficoll 70 showed optimal results at specific concentrations, correlating with domain dynamics and rigidity.
Area of Science:
- Biochemistry
- Biophysics
- Molecular Biology
Background:
- Macromolecular crowding significantly influences biological macromolecules within cells.
- Understanding enzyme function in crowded cellular environments is crucial for comprehending biological processes.
Purpose of the Study:
- To investigate the impact of various crowders on the activity and dynamics of the multidomain enzyme AK3L1 (adenylate kinase).
- To correlate changes in enzyme activity with domain displacement and solvation properties under crowding conditions.
Main Methods:
- Enzyme kinetics assays (Michaelis Menten plots) to determine kinetic parameters (Km, Vmax).
- Ensemble Förster Resonance Energy Transfer (FRET) studies to analyze domain (LID and CORE) displacements.
- Solvation studies using CPM probe to assess protein matrix rigidity.
Main Results:
- Crowders generally enhanced AK3L1 activity, altering Km and Vmax values.
- Ficoll 70 demonstrated maximum enzyme activity enhancement at 100 g/L, with higher concentrations reducing activity.
- Increased protein matrix rigidity, particularly with Ficoll 70, correlated with decreased enzyme activity.
Conclusions:
- A distinct correlation exists between domain displacement, enzyme activity, and molecular dynamics in crowded environments.
- Macromolecular crowding profoundly modulates enzyme function, highlighting the need for further studies on enzymes in complex cellular milieus.
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