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Updated: Jul 20, 2026
09:42
Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
Published on: January 16, 2016
Solution NMR and computer simulation studies of active site loop motion in triosephosphate isomerase
Francesca Massi1, Chunyu Wang, Arthur G Palmer
1Department of Biochemistry and Molecular Biophysics, Columbia University, 630 West 168th Street, New York, New York 10032, USA.
Biochemistry
|September 7, 2006
Summary
Triosephosphate isomerase (TIM) dynamics were studied using NMR and simulations. Key regions show conformational changes on the micro- to millisecond timescale, revealing insights into enzyme function.
Area of Science:
- Biochemistry
- Structural Biology
- Computational Biology
Background:
- Triosephosphate isomerase (TIM) is a crucial enzyme in glycolysis.
- Understanding enzyme dynamics is key to elucidating function.
- Conformational flexibility can impact catalytic efficiency.
Purpose of the Study:
- To investigate the dynamic behavior of TIM in complex with glycerol 3-phosphate (G3P).
- To identify regions exhibiting conformational transitions.
- To correlate dynamic processes with enzyme function.
Main Methods:
- Solution Nuclear Magnetic Resonance (NMR) spin relaxation experiments.
- Classical Molecular Dynamics (MD) simulations.
- Analysis of chemical exchange broadening effects in NMR spectra.
Main Results:
- Three distinct regions in TIM (Lys 84, active site loop 6, helix G) show micro- to millisecond timescale conformational transitions.
- Loop 6 exhibits correlated opening and closing motions.
- Helix G transitions involve changes between 3(10)- and alpha-helical structures.
Conclusions:
- NMR and MD simulations provide a global view of TIM's conformational dynamics.
- These dynamics are intrinsically linked to the enzyme's function.
- The study highlights the importance of dynamic processes in enzyme mechanisms.
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