The effect of proteolysis on the calmodulin activation of cyclic nucleotide phosphodiesterase
| Autor: | J B Robinson, E Stellwagen, M M Tucker |
|---|---|
| Rok vydání: | 1981 |
| Předmět: |
chemistry.chemical_classification
Conformational change Protease medicine.diagnostic_test Calmodulin biology Cyclic nucleotide phosphodiesterase Proteolysis medicine.medical_treatment Cell Biology Trypsin Biochemistry Enzyme chemistry Affinity chromatography medicine biology.protein Molecular Biology medicine.drug |
| Zdroj: | Journal of Biological Chemistry. 256:9051-9058 |
| ISSN: | 0021-9258 |
| DOI: | 10.1016/s0021-9258(19)52506-6 |
| Popis: | A high Km cytoplasmic cyclic nucleotide phosphodiesterase (EC 3.4.1.17) has been obtained from bovine brain. The unproteolyzed enzyme contains (63 +/- 1) X 10(3) molecular weight polypeptide chains which exhibit little if any basal catalytic activity. Complexation with calmodulin stimulates the catalytic activity nearly 2 orders of magnitude, presumably, by causing a conformational change in the enzyme which either creates or exposes the catalytic sites. Removal of about 120 amino acids from the terminal portion(s) of each polypeptide chain either by an endogenous protease or by exogenous trypsin prevents calmodulin complexation and generates a basal catalytic activity equivalent to that of the unproteolyzed enzyme-calmodulin complex. In contrast to affinity chromatography using immobilized calmodulin, blue dextran-Sepharose chromatography can be used to select for enzyme containing only unproteolyzed polypeptide chains. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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