Isosafrole serves as an excellent inducing agent in rabbits for Wq, the same isozyme as that which is induced by 3-methylcholanthrene and 5,6-benzoflavone. Since the isosafrole adduct formed with isozyme 4 is unstable, the uncomplexed cytochrome may be purified in very good yield (over 30%, based on total P-450) from liver microsomes of animals given this agent. Isosafrole forms adducts with bo...

Vertebrates have acidic and basic isozymes of adenylosuccinate synthetase, which participate in the first committed step of de novo AMP biosynthesis and/or the purine nucleotide cycle. These isozymes differ in their kinetic properties and N-leader sequences, and their regulation may vary with tissue type. Recombinant acidic and basic synthetases from mouse, in the presence of active site ligand...

Chronic stimulation of a predominantly fast skeletal muscle enhanced the expression of type I (slow muscle) Ca-ATPase and suppressed the expression of the type II (fast muscle) Ca-ATPase. Monoclonal antibodies IID8 and IIH11 against type I (slow) and type II (fast) isozymes respectively, were used to type the Ca-ATPases of the isolated SR (sarcoplasmic reticulum) by Western blots, and the Ca-AT...

The previous studies of the interaction of purine analogs and human erythrocyte acid phosphatase isozymes were extended to include erythrocyte acid phosphatase from seven other species. Consistent responses, similar to the observations with the several genotypically different human isozymes, were observed. The isozyme from chimpanzee erythrocytes was similar to the human B-type isozyme while th...

The cytosolic aldehyde dehydrogenase (ALDH) isozyme from cyclophosphamide (f PA) resistant 1.1210 cells (L1210/CPA) was purified to apparent homogeneity using ternary enzyme complex-dye ligand chromatography. The purified isozyme migrates as a single band at M, 51,000 in sodium dodecyl sulfate polyacrylamide gel electrophoresis and as a single charge species at isoelectric point = 5.8 in isoele...

Adenylate kinase activity (ATP:AMP-phosphotransferase, EC 2.7.4.3) was studied in subcellular extracts of rat liver tissue. Essentially all of the activity, over 150 units per g of tissue, wet weight (1.7 units per mg of protein), was released into the cytosol when the tissue was homogenized in 0.025 M sucrose. Isotonic (0.25 M sucrose) homogenization and separation of subcellular fractions by ...

Recently, it has been reported that mitochondria possess a novel pathway for nitric oxide (NO) synthesis. This pathway is induced when cells experience hypoxia, is nitrite (NO(2)(-))-dependent, is independent of NO synthases, and is catalyzed by cytochrome c oxidase (Cco). It has been proposed that this mitochondrially produced NO is a component of hypoxic signaling and the induction of nuclear...