Myosin isoforms in normal and dystrophic chickens

The myosin isoform content in the affected fibers of chickens with inherited muscular dystrophy has been investigated with a new high-performance liquid chromatographic procedure for separation of the tryptic fragments of myosin subfragment 1 (S-1). The results indicate that dystrophic muscle contains substantial amounts of normal adult myosin, together with various myosin species present in normal 5-day posthatch chickens. Confirmation was obtained by comparative peptide mapping of the S-1 tryptic fragments and by N-terminal sequencing of 20-kDa species. Together with data on other contractile proteins and certain metabolic enzymes [Obinata, T., Takano-Ohmura, H., & Matsuda, R. (1980) FEBS Lett. 120, 195-198; Mikasa, T., Takeda, S., Shimizu, T., & Kitaura, T. (1981) J. Biochem. (Tokyo) 89, 1951-1962; Feit, H., & Domke, R. (1982) Cell Motil. 2, 309-315; Cosmos, E. (1966) Dev. Biol. 13, 163-181; Cosmos, E., & Butler, J. (1967) in Exploratory Concepts in Muscular Dystrophy and Related Disorders (Milhorat, A. R., Ed.) pp 197-204, Excerpta Medica, Amsterdam], the results are consistent with the hypothesis that there is a general defect in muscle maturation in avian dystrophy.     

Superoxide dismutase activity in nematodes

The activities of the enzymes superoxide dismutase (E.C.:1.15.1.1) and catalase (E.C.:1.11.1.6) were studied in purified extracts of four nematodes: Ascaris suum, Toxascaris leonina, Toxocara canis and T. cati adult males and females. No catalase activity was found in any of the extracts. The results reveal that the SOD activities of the four parasites presented species differences and also sexual differences within each species. Polyacrylamide gel electrophoresis pattern analysis confirmed that the mobilities, widths and band intensities varied according to the species and sex of the parasite from which the enzyme was obtained.     

Superoxide dismutase activity in transgenic canola

Superoxide dismutase (SOD) activity was investigated in leaves of transgenic canola plants which expressed heterologous genes of different origin, namely 1—herbicide resistance genes (bar and simultaneously bar and epsps); 2—DesC desaturase gene (desC) of cyanobacterium Synechococcus vulcanus; 3—human interferon α2b gene (huIFN-α2b); 4—esxA::fbpB ^ΔTMD fused gene, encoding ESAT-6 and Ag85b Mycobacterium tuberculosis proteins, inducing immune response against tuberculosis; 5—cyp11A1 gene of cytochrome P450_SCC from bovine adrenal cortex mitochondria. Introduction of herbicide resistance genes as well as desaturase gene of cyanobacterium and mycobacterium’s genes did not change leaf SOD activity. At the same time it was shown that cyp11A1 and huIFN-α2b canola have increased leaf SOD activity up 58 and 33%, respectively, compared with control ones in non-stress conditions. It may be a prerequisite for improved resistance of these plants to the stressors of different origin.     

Superoxide dismutase activity of digestive secretions

A superoxide dismutase (SOD) activity in saliva and gastric juice has been revealed using the NBT reduction and adrenaline autooxidation assays. This activity in saliva is induced mainly by enzymic mechanisms, whereas in gastric juice--by nonenzymic mechanisms. The gel chromatographic analysis of saliva has demonstrated the presence of several SOD isoenzymes. Nonenzymic mechanisms of the SOD activity in gastric juice involve the ionic activity of H+, Cu2+ and that of reduced glutathione. The SOD activity in gastric juice can be decreased by adding antacids and Fe ions. The effect of Fe3+ is found to be different depending on the methods of the SOD activity evaluation. Such metal-chelating agents as histidine and organic acids increase the SOD activity in gastric juice.     

Superoxide dismutase activity in nerve cell culture

Superoxide dismutase (EC 1.15.1.1) activity was assayed in preparations obtained from several clonal lines of nerve cell culture, by enzymatic and nonenzymatic assays. The enzyme was found in dialyzed homogenates of washed cells and in partially purified fractions. The enzyme was also found in cells which had been grown in media containing 5-bromodeoxyuridine, where cell differentiation was observed.     

Superoxide dismutase activity in copper-deficient swine.

These experiments demonstrate the dependency of cuprozinc superoxide dismutase activity in red cells and liver on an adequate dietary intake of copper. The superoxide dismutase activity in red cells decreased to 15% of control values and, therefore, these cells may be used as a convenient model for studying the physiologic consequences of free radicals     

Superoxide dismutase activity of the captopril-iron complex

With an assay that generates superoxide anion radicals without the intervention of metal ions we investigated the antioxidant properties of captopril, an angiotensin-converting enzyme inhibitor with a sulfhydryl group. Under these conditions, increasing concentrations of the drug were seen not to scavenge O· ₂ ^– directly. However, a combination of captopril and iron could bring about the breakdown of the superoxide anion; a result that may help to understand the free radical-scavenging properties of captopril.     

Superoxide dismutase activity of cytochrome oxidase.

Cytochrome oxidase preparations have weak but not negligible superoxide dismutase activity which is inhibited by cyanide and azide as well as alkaline and thermal treatments. The activity does not depend on lipid content of cytochrome oxidase preparations. The activity, probably, cannot be explained by extraneous copper.     

Superoxide dismutase activity of macrocyclic polyamine complexes

Copper(II) and nickel(II) complexes of macrocyclic polyamine derivatives possessing partial oligopeptide-like structures are found to suppress the xanthine-xanthine oxidase-mediated reduction of nitroblue tetrazolium and also to suppress formazan formation by potassium superoxide. The activity in the superoxide dismutase assay is dependent on ring size, type and number of donor atoms, metal ion, and substituents on the macrocycles. Some of those are more active than the known O₂^? scavengers such as copper(II)-salicylate and copper(II)-amino acid (or peptide) complexes. Nickel (II)-naphthylmethyl-dioxo-[16]ane N₅, 13, 1 : 1 complex (NiH_?2L) is the most active among the 30 chelates examined.     

Superoxide dismutase activity in salt stressed wheat seedlings

We investigated the effect of salt stress on enzymatic activity of superoxide dismutase (SOD) isozymes in shoot and root tissues of salt tolerant and sensitive wheat (Triticum aestivum L. and Triticum durum Defs.) cultivars. Ten day old seedlings were subjected to 0.7 M NaCl stress for 3 and 5 days. Seedlings treated in the same manner without salt stress served as controls. Activity of SOD isozymes in root and shoot extracts was determined by activity staining of native polyacrylamide gels. In both shoot and root extracts of examined cultivars two isozymes of SOD, namely MnSOD and Cu/ZnSOD were identified. Cu/ZnSOD activity comprised 90 % of total SOD activity in both root and shoot tissues. Salt stress caused 1–1.5 fold increase in MnSOD activity of shoots in tolerant cultivars when compared with non-stressed controls. Under stress conditions, compared to controls all cultivars exhibited reduced MnSOD activity in root tissues. Cu/ZnSOD activity, on the other hand, was remarkably enhanced (3–4 fold) in root extracts of the tolerant cultivars, whereas it was reduced in the sensitive ones.     

Superoxide dismutase in normal and malignant tissues in different species.

1. Superoxide dismutase (superoxide: superoxide oxido-reductase, E.C. 1.15.1.1) in different species was determined quantitatively and qualitatively. Although quantitative differences were minor, there were significant differences in the isoenzyme patterns among the species. 2. No quantitative differences were found in superoxide dismutase (SOD) activities in the brains of mice between 1 and 23 days of age. The mitochondrial isoenzyme increased with age, attaining maximal levels between 9 and 12 days. In the six, regions of adult rat brain studied, highest values of SOD were found in the hypothalamus and lowest in the cortex. 3. SOD levels generally were lower in several transplantable mouse and rat tumors than in normal tissues of these species. Mn-SOD was not detected in the tumors studied by the methods employed.     

Superoxide dismutase activity and photosensitizing properties of 2,5-dihydroxybenzolsulfonate

2,5-dihydroxybenzolsulphonate was shown to actively interact with the superoxide radical O2-. formed under UV-radiation of glycyltryptophan aqueous solutions or under visible light illumination of glycyltryptophan and riboflavine. The constant of the rate of reaction of 2,5-dihydroxybenzolsulphonate with O2-. was determined to be equal to 1.3 X 10(9) M-1s-1. A photosensitized effect of 2,5-dihydroxybenzolsulphonate under illumination with the light with 280 nm was found. The sensitization efficiency of glycyl-tryptophan oxidation increases when the experiments are carried out in the oxygen atmosphere.