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High-throughput Measurement of Dictyostelium discoideum Macropinocytosis by Flow Cytometry
Published on: September 10, 2018
Multiple forms of glucokinase from Dictyostelium discoideum
Journal of Bacteriology
|February 1, 1978
Summary
Two forms of glucokinase were identified in cellular extracts. Aggregating cells contained one form, while culminating cells had two distinct glucose-phosphorylating enzymes with different kinetic properties.
Area of Science:
- Biochemistry
- Molecular Biology
- Cellular Metabolism
Background:
- Glucokinase plays a crucial role in glucose metabolism.
- Understanding the different forms of glucokinase is important for studying cellular energy regulation.
Purpose of the Study:
- To investigate the presence and kinetic properties of glucokinase in different cellular stages.
- To identify distinct glucose-phosphorylating enzymes during cell aggregation and culmination.
Main Methods:
- Enzyme kinetic assays to determine Km values for glucose.
- Electrophoretic analysis to distinguish between enzyme forms.
- Preparation of cellular extracts from aggregating and culminating cells.
Main Results:
- A single glucokinase form with a Km of 0.12 mM glucose was found in aggregating cells.
- Culminating cells exhibited two glucose-phosphorylating enzymes: the original form and a second enzyme with a Km of approximately 0.01 mM glucose.
Conclusions:
- Cellular differentiation involves changes in glucokinase expression and activity.
- The presence of a high-affinity glucokinase in culminating cells suggests a role in enhanced glucose uptake during this stage.
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