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Updated: Jun 8, 2026
08:57
Simultaneous Measurement of Superoxide/Hydrogen Peroxide and NADH Production by Flavin-containing Mitochondrial Dehydrogenases
Published on: February 24, 2018
Characterizing the dynamics of functionally relevant complexes of formate dehydrogenase
Jigar N Bandaria1, Samrat Dutta, Michael W Nydegger
1Department of Chemistry and Optical Science and Technology Center, University of Iowa, Iowa City, IA 52242, USA.
Summary
Enzyme active site motions on the picosecond timescale are controversial. This study used 2D IR spectroscopy to show formate dehydrogenase
Area of Science:
- Biochemistry
- Enzyme kinetics
- Spectroscopy
Background:
- Enzyme-catalyzed reaction rates may be influenced by femtosecond to picosecond timescale motions.
- Experimentally characterizing these motions in enzyme active sites is challenging.
Purpose of the Study:
- To investigate the role of picosecond timescale motions in enzyme catalysis.
- To characterize active-site motions in formate dehydrogenase complexes.
Main Methods:
- Utilized two-dimensional infrared (2D IR) spectroscopy.
- Studied complexes of formate dehydrogenase with the transition-state-analog inhibitor azide (N(3)(-)).
- Analyzed frequency-frequency time correlation functions (FFCF).
Main Results:
- Ternary complexes with NAD(+) and NADH showed complete FFCF decay with time constants of 3.2 ps and 4.6 ps, respectively.
- This indicates a narrow, rigid conformational distribution near the transition state.
- Binary complexes exhibited a static contribution to FFCF, suggesting slower motions beyond the measurement window.
Conclusions:
- The enzyme active site is well-organized at the transition state, with limited picosecond motions.
- This suggests that slow motions, not picosecond dynamics, may be more relevant for other enzyme complexes.
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