The effect of ligands (glucose, ATP and Mg2+) and zwitterionic micellesof lysophosphatidylcholine (LPC) or N-hexadecyl-N,N-dimethyl-3-ammoniumpropanesulfonate (HPS) in the yeast hexokinase (HK) stability was studied at35°C. The thermal inactivation kinetics followed one-exponentialdecay. The effect of ligands on protecting the enzyme against inactivationfollowed the order: glucose>glucose/Mg2+>ATP/Mg2+≌Mg2+≌bufferonly. Both LPC and HPS micelles increased the enzyme stability only whenthe incubation medium contained glucose or glucose/Mg2+,suggesting that the protein conformation is a key prerequisite for theenzyme-micelle interaction to take place. This enzyme-micelle interactionresulted in an increased catalytic efficiency (with a decrease in Km forATP and increase in Vmax as well as in changes on the tertiary (intrinsicfluorescence) structure of the yeast hexokinase.
Increased Stability and Catalytic Efficiency of Yeast Hexokinase Upon Interaction with Zwitterionic Micelles. Kinetics and Conformational Studies
- Views Icon Views
- Share Icon Share
- Cite Icon Cite
Rodrigo Guerra, M. Lucia Bianconi; Increased Stability and Catalytic Efficiency of Yeast Hexokinase Upon Interaction with Zwitterionic Micelles. Kinetics and Conformational Studies. Biosci Rep 1 February 2000; 20 (1): 41–49. doi: https://doi.org/10.1023/A:1005583117296
Download citation file: