Article
Analysis of hydride transfer and cofactor fluorescence decay in mutants of dihydrofolate reductase: possible evidence for participation of enzyme molecular motions in catalysis.
Biochemistry - 10 Dec 1991
Farnum M F, Magde D, Howell E E, Hirai J T, Warren M S, Grimsley J K, Kraut J
Abstract excerpt
A remarkable correlation has been discovered between fluorescence lifetimes of bound NADPH and rates of hydride transfer among mutants of dihydrofolate reductase (DHFR) from Escherichia coli. Rates of hydride transfer from NADPH to dihydrofolate change by a factor of 1,000 for the series of mutant enzymes. Since binding constants for the initial complex between coenzyme and DHFR change by only a factor of 10, the...
Topics
- Catalysis
- Coenzymes
- Kinetics
- Macromolecular Substances
- Models, Molecular
- Mutation
- NADP
- Oxidation-Reduction
- Protein Binding
- Solutions
- Spectrometry, Fluorescence