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Dictyostelium calmodulin: affinity isolation and characterization.

G A Jamieson·W A Frazier
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Abstract

The Ca2+-binding regulatory protein calmodulin (CaM) has been purified from the cellular slime mold, Dictyostelium discoideum. Isolation of homogeneous Dictyostelium CaM was accomplished in high yield by ion-exchange chromatography and Ca2+-dependent affinity chromatography on phenothiazine-Sepharose 4B. This isolate has been demonstrated to possess the following physicochemical and functional properties characteristic of other CaM isolates: (i) a molecular weight ca. 16,000; (ii) an amino acid composition similar to other CaMs--with the notable exception that Dictyostelium CaM, as first determined by Bazari and Clarke [(1981) J. Biol. Chem. 256, 3598-3603] lacks the single trimethylated lysine (Tml) residue identified in nearly all CaMs purified to date; (iii) a CNBr peptide map similar to that of other CaMs; (iv) a Ca2+-dependent shift in migration during native- and sodium dodecyl sulfate-polyacrylamide gel electrophoretic analyses; (v) ability to form Ca2+-dependent complexes with rabbit skeletal muscle troponin I; and (vi) ability to activate in a Ca2+-dependent manner bovine brain cyclic nucleotide phosphodiesterase.

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Amino AcidsAnimalsBrainCalmodulinCattleChemical PhenomenaChemistryChromatography, AffinityDictyosteliumElectrophoresis, Polyacrylamide GelEnzyme ActivationProtein BindingRabbitsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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G A Jamieson, W A Frazier. 1983. Dictyostelium calmodulin: affinity isolation and characterization.. https://doi.org/10.1016/0003-9861(83)90490-3

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