Plant class III peroxidase (PRX) catalyzes the oxidation and oxidative polymerization of a variety of phenolic compounds while reducing hydrogen peroxide. PRX proteins are classified into apoplast type and vacuole type based on the absence or the presence of C-terminal propeptides, which probably function as vacuolar sorting signals (VSSs). In this study, in order to improve our understanding o...

Agents such as prostaglandins E1 and I2 which elevate cAMP levels in platelets also increase cAMP phosphodiesterase activity. Since much of the cAMP phosphodiesterase activity in human platelets is due to the cGMP-inhibited isozyme (Macphee, C. H., Harrison, S. A., and Beavo, J. A. (1986) Proc. Natl. Acad. Sci. U. S. A. 83, 6600-6663), we examined the regulation of this isozyme by prostaglandin...

Six cathepsin D isozymes have been purified from porcine spleen using a large scale purification procedure. Five isozymes, I to V, have an identical molecular weight of 50,000 and are similar in specific activity. Isozymes I to IV contained two polypeptide chains each. The light and heavy chains have Mr = 15,000 and 35,000, respectively. Isozyme V is a single polypeptide. The molecular weight o...

Received April 12,1978 SUMMARY Isoproterenol injection produces cardiac hypertrophy and salivary gland enlargement in rats. After subcutaneous injection (5 mg/kg) twice daily for 10 days, the soluble extracts from these and other tissues were subjected to DEAE-cellulose chromatography and the activity of isozymes I and II of cyclic AMP-dependent protein kinase was measured. The activity of isoz...

Glycogen synthase, the rate-limiting enzyme in glycogen biosynthesis, has been postulated to exist as isozymes in rabbit liver and muscle (Camici, M., Ahmad, Z., DePaoli-Roach, A. A., and Roach, P. J. (1984) J. Biol. Chem. 259, 2466-2473). Both isozymes share a number of properties including multiple phosphorylation of the enzyme subunit. In the present study, we determined the amino acid seque...

Ca2#/calmodulin-dependent protein kinase II (CaMKII) isozyme variability is the result of alternative usage of variable domain sequences. Isozyme expression is cell type-specific to transduce the appropriate Ca2# signals. We have determined the subcellular targeting domain of "E CaMK-II, an isozyme that induces neurite outgrowth, and of a structurally similar isozyme, !C CaMK-II, which does not...

A novel matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry method has been developed to quantitate cytochrome P450 (P450) isozymes based on their unique isozyme-specific tryptic peptides. It was shown that the molar ratio of P450 isozyme-specific peptides is linearly proportional to the mass peak area ratio of corresponding peptides not only in simple two-p...

The Fusarium wilt caused by Fusarium oxyspoum f. sp. cubense (Foc) is a major biotic constraint for banana production. The characteristics of F. oxyspoum f. sp. cubense isolates were investigated using electrophoretic studies of isozyme and whole-cell protein. The morphological characteristics of the isolates were very similar to each other. All the Foc isolates were pathogenic to banana cultiv...

The rat prostate, a classical androgen-target tissue, contains both known isozymes of steroid 5alpha-reductase. i.e. type I and type II. So far, the role of the type I isozyme has been proposed as catabolic. The abundant expression of type I 5alpha-reductase in an androgen-target tissue is therefore puzzling. Assessment of the subcellular localization of 5alpha-reductase isozymes in rat prostat...

The dwarf mutation in mice interferes with the development of those anterior pituitary cells responsible for production of thyroid stimulating hormone, growth hormone, and prolactin. Myosin isozyme transitions in both cardiac and skeletal muscle were also found to be affected in this mutant. Electrophoresis of native myosins demonstrated that the fetal (V3) to adult (V1) ventricular cardiac iso...