title: Calmodulin-dependent cyclic nucleotide phosphodiesterase from bovine eye: high calmodulin affinity isozyme immunologically related to the brain 60-kDa isozyme.
abstract: Calmodulin-dependent cyclic nucleotide phosphodiesterase was identified in and purified to apparent homogeneity from the total calmodulin-binding protein fraction of bovine eye in a single step by immunoaffinity chromatography. The bovine eye calmodulin-dependent cyclic nucleotide phosphodiesterase is immunologically similar to the bovine brain 60-kDa isozyme. The purified enzyme had higher affinity for calmodulin than the 60-kDa phosphodiesterase isozyme from bovine brain, but similar affinity to that of the heart isozyme. When the Ca(2+)-dependence of the eye enzyme was compared to cardiac calmodulin-dependent cyclic nucleotide phosphodiesterase at an identical concentration of calmodulin, the bovine eye calmodulin-dependent cyclic nucleotide phosphodiesterase was activated at the same Ca2+ concentration as the bovine heart calmodulin-dependent cyclic nucleotide phosphodiesterase isozyme.
authors.affiliation: Department of Pathology, College of Medicine, University of Saskatchewan, Saskatoon, Canada.
authors.forename: R K
authors.initials: RK
authors.lastname: Sharma
authors.forename: Y
authors.initials: Y
authors.lastname: Tan
authors.forename: R V
authors.initials: RV
authors.lastname: Raju
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology; D002118:Calcium / Q000378:metabolism; D002147:Calmodulin / Q000037:antagonists & inhibitors / Q000378:metabolism; D002417:Cattle; D002614:Chelating Agents / Q000494:pharmacology; D054677:Cyclic Nucleotide Phosphodiesterases, Type 1; D004533:Egtazic Acid / Q000494:pharmacology; D004789:Enzyme Activation; D005123:Eye / Q000201:enzymology*; D007527:Isoenzymes / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D007700:Kinetics; D008970:Molecular Weight; D010727:Phosphoric Diester Hydrolases / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology
chemical_list: D002147:Calmodulin; D002614:Chelating Agents; D007527:Isoenzymes; D003189:p-Methoxy-N-methylphenethylamine; D004533:Egtazic Acid; D010727:Phosphoric Diester Hydrolases; D054677:Cyclic Nucleotide Phosphodiesterases, Type 1; D002118:Calcium