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...

Powdery mildew infection in cucumber plants was significantly reduced by foliar application of 2,6dichloroisonicotinic acid (INA). Although the overall isozyme banding patterns of superoxide dismutase (SOD) and peroxidase (POD) were very similar, there were differences in the densities of major bands between the leaves of control and INA-applied plants. When plants were subjected to foliar appl...

To determine whether thymidine kinase (TK) isozyme status adds clinically useful information in adult nonHodgkin’s lymphoma (NHL). we have analyzed peripheral blood plasma and lymphocytes of 44 patients with NHL for either TK1 or TK2 isozyme activity. On the basis of isozyme status. patients could be divided into two groups that did not differ significantly with respect to known determinants fo...

A novel assay procedure has been developed to allow simultaneous activity discrimination in crude tissue extracts of the three known mammalian nicotinamide mononucleotide adenylyltransferase (NMNAT, EC 2.7.7.1) isozymes. These enzymes catalyse the same key reaction for NAD biosynthesis in different cellular compartments. The present method has been optimized for NMNAT isozymes derived from Mus ...

Two isozymes of glutamate dehydrogenase were shown to exist in a thermophilic strain of Chlorella pyrenoidosa. The NADPH:NADH activity ratios of the NADHand NADPHspecific isozymes were 1: 5 and 33: 1, and the molecular weights were estimated to be 179,000 and 269,000, respectively. Only the NADH-specific isozyme was detectable in nitrate-cultured cells; the synthesis of the NADPH-specific isozy...