Calmodulin-dependent cyclic nucleotide phosphodiesterase was purified from bovine brain to apparent homogeneity by a new procedure involving DEAE-cellulose, Affi-Gel blue, calmodulin-Sepharose 4B, and Sephadex G-200 column chromatographies. The enzyme more than 3,000-fold the extracts with greater 12% yield. could be activated 10- 15-fold calmodulin Ca2+ specific activity of 300 mumol cAMP hydrolyzed/min/mg protein. Molecular weight determined 115,800 sedimentation equilibirum method or...

A protein which can associate with the Ca”-dependent modulator resulting in inhibition of Ca’+-activatable cyclic nucleotide phosphodiesterase has been discovered recently and designated as binding (Wang, J. H., Desai, R. (1977) Biol. Chem. 252,4175-4183; Klee, C. B., Krinks, M. H. (1978) Biochemistry 17, 120-126). This is purified from bovine brain to near homogeneity. The purification procedure based mainly on Ca’+dependent association this highly acidic protein. shown be a globular...

Kinetic studies on the activation of cyclic nucleotide phosphodiesterase (3',5'-cyclic-nucleotide 5'-nucleotidohydrolase, EC 3.1.4.17) as a function calmodulin and Ca2+ concentrations have been carried out. A general approach to analyzing mechanism activation, which takes into consideration various interactions among liganded with differing degrees, is presented. The method applicable other calmodulin-regulated enzyme systems. Our kinetic analysis reveals that all four must be bound for...

Purified bovine brain calmodulin-dependent cyclic nucleotide phosphodiesterase (3',5'-cyclic-nucleotide 5'-nucleotidohydrolase, EC 3.1.4.17) contains isozymes that are composed of two distinct subunits with molecular masses 60,000 and 63,000 daltons. Analysis by NaDodSO4 gel electrophoresis autoradiography a sample phosphorylated in the presence [32P]ATP heart cAMP-dependent protein kinase catalytic subunit revealed only 60-kDa was phosphorylated. By using an isozyme preparation greatly...

Bovine brain contains calmodulin-dependent cyclic nucleotide phosphodiesterase isozymes which are composed of two distinct subunits: Mr 60,000 and 63,000. The 60-kDa but not the 63-kDa subunit-containing isozyme can be phosphorylated by cAMP-dependent protein kinase resulting in decreased affinity this subunit toward calmodulin (Sharma, R. K., Wang, J. H. (1985) Proc. Natl. Acad. Sci. U. S. A. 82, 2603-2607). In contrast, purified has been found to a preparation bovine calmodulin-binding...

N-Myristoyltransferase (NMT) transfers myristate to an amino-terminal glycine of many eukaryotic proteins. In yeast, worms, and flies, this enzyme is essential for viability the organism. Humans mice possess two distinct but structurally similar enzymes, NMT1 NMT2. These enzymes have peptide specificities, no one has examined functional importance in vivo. To address issue, we performed both genetic biochemical studies. Northern blots with RNA from adult situ hybridization studies day 13.5...

Abstract The 63-kDa subunit, but not the 60-kDa of brain calmodulin-dependent cyclic nucleotide phosphodiesterase was phosphorylated in vitro by autophosphorylated form Ca2+/calmodulin-dependent protein kinase II. When calmodulin bound to phosphodiesterase, 1.33 +/- 0.20 mol phosphate incorporated per subunit within 5 min with no significant effect on enzyme activity. Phosphorylation presence low concentrations resulted a phosphorylation stoichiometry 2.11 0.21 and increased about 6-fold...

An inhibitor protein of cyclic nucleotide phosphodiesterase is demonstrated in bovine brain extract and separated from modulator binding protein, a recently discovered inhibitory factor phosphodiesterase.The new similar to the AMP retina (Dumler, I. L., Etingof, F.

Abstract Biosynthetic l-threonine dehydratase (l-threonine hydrolyase, deaminating, EC 4.2.1.16) has been purified about 2500-fold from extracts of spinach leaves by ammonium sulfate fractionation, controlled heat treatment, and chromatography on triethylaminoethyl cellulose hydroxylapatite. The feedback control other properties the enzyme are essentially same as that native enzyme. Although is active both l-serine, former preferred substrate. ratio two activities remains throughout...

Background : Colorectal cancer is one of the leading causes death in North America. Since treatment colonic remains difficult because lack effective chemotherapeutic agents, it important to continue search for cellular functions that can be disrupted by drugs and inhibit development or progression this disease. Modification proteins myristoylation has been recognized as function various viral, oncogenic, signal-transduction thus proposed a target drug design. However, activity enzyme...

Calpains represent a well-conserved family of Ca2+ -dependent proteolytic enzymes. Recently, the importance calpain in metastatic process has received great attention. To investigate whether m-calpain contributes to pathogenesis colorectal cancer, we investigated expression and its inhibitors, calpastatin high-molecular-weight calmodulin-binding protein (HMWCaMBP), human surgical specimens.Fifty cases colon carcinoma were evaluated for this study. Of 50 evaluated, presented report six...

A rabbit lung cyclic nucleotide phosphodiesterase (PDE) prepared by successive chromatography on DEAE-cellulose and G-200 Sephadex columns in the presence of EGTA was activated Ca2+ contained calmodulin (CaM), suggesting that enzyme exists as a stable CaM.PDE complex (Sharma, R.

Abstract Purpose: Melanoma is a solid tumor that notoriously resistant to chemotherapy, and its incidence rapidly increasing. Recently, several signaling pathways have been shown contribute melanoma tumorigenesis, including constitutive activation of mitogen-activated protein kinase, Akt, Stat-3. The multiple may account in part for the difficulty treatment melanoma. In recent screen compounds, we found an organopalladium compound, Tris (dibenzylideneacetone) dipalladium (Tris DBA), showed...

Myristoyl-CoA:protein<i>N-</i>myristoyltransferase (NMT, EC 2.3.1.97) catalyzes the co-translational addition of myristic acid to amino-terminal glycine residue a number important proteins diverse functions. We have isolated full-length <i>Arabidopsis thaliana</i>cDNA encoding NMT (<i>AtNMT1</i>), first described from higher plant. This <i>AtNMT1</i> cDNA clone has an open reading frame 434 amino acids and predicted molecular mass 48,706 Da. The primary structure is 50% identical mammalian...