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05:51
Direct Detection of the Acetate-forming Activity of the Enzyme Acetate Kinase
Published on: December 19, 2011
Phosphorylation of Acinetobacter isocitrate lyase
1Department of Microbiology, Arizona State University, Tempe 85287-2701.
Biochemical and Biophysical Research Communications
|January 15, 1992
Summary
Acinetobacter calcoaceticus regulates metabolic pathways using isocitrate dehydrogenase (form II) and isocitrate lyase. Phosphorylation of isocitrate lyase may control the glyoxylate bypass, a key metabolic route.
Area of Science:
- Biochemistry
- Microbiology
- Metabolic Regulation
Background:
- Acinetobacter calcoaceticus exhibits two forms of isocitrate dehydrogenase during succinate growth.
- Acetate addition to succinate-grown cultures induces significant increases in isocitrate dehydrogenase (form II) and isocitrate lyase activity.
Purpose of the Study:
- To investigate the phosphorylation of isocitrate lyase in Acinetobacter calcoaceticus.
- To explore the potential regulatory role of isocitrate lyase phosphorylation in the glyoxylate bypass.
Main Methods:
- Enzyme activity assays for isocitrate dehydrogenase and isocitrate lyase.
- Analysis of enzyme phosphorylation in Acinetobacter calcoaceticus.
Main Results:
- Form II isocitrate dehydrogenase activity is upregulated by acetate, suggesting a role in isocitrate partitioning.
- The phosphorylation of isocitrate lyase was characterized in Acinetobacter calcoaceticus.
Conclusions:
- Isocitrate dehydrogenase form II may regulate the flow of metabolites between the TCA cycle and the glyoxylate bypass.
- Enzyme phosphorylation represents a potential regulatory mechanism for the glyoxylate bypass in Acinetobacter calcoaceticus.
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