Distinctive properties of glutamine synthetase from the cyanobacterium Anacystis nidulans
| Autor: | R. J. Cedergren, Normand Rondeau, Diane Emond |
|---|---|
| Rok vydání: | 1979 |
| Předmět: |
chemistry.chemical_classification
Ammonium sulfate Cell Membrane General Medicine Biology Cyanobacteria Enterobacter aerogenes biology.organism_classification chemistry.chemical_compound Enzyme Biochemistry chemistry Glutamate-Ammonia Ligase Ionic strength Glutamine synthetase Transferase Centrifugation Adenylylation |
| Zdroj: | Canadian Journal of Biochemistry. 57:843-851 |
| ISSN: | 0008-4018 |
| DOI: | 10.1139/o79-104 |
| Popis: | The intracellular levels of glutamine synthetase (GS) in Anacystis nidulans grown under different conditions were determined using a whole-cell assay. Nitrate-grown cells have 64% more GS than cells grown in ammonium sulfate. Nitrogen starvation does not affect GS levels appreciably. Incubation of nitrate-grown cells with ammonium sulfate does not change the ratio of γ-glutamyl transferase activities stimulated by Mg2+ and Mn2+ ions. An in vitro test of adenylylation indicates that algae do not have an endogenous adenylyl transferase (ATase) and that algal GS is not adenylylatable by the Klebsiella aerogenes ATase. Some characteristics of the GS–membrane complex were determined by centrifugation of the complex under varying conditions of pH and ionic strength. In this way, it was shown that acid pH (4.5) stabilizes the complex and high ionic strength tends to solubilize the enzyme. A simple partial purification of GS (89-fold) was developed based on the sedimentation properties of GS. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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