Showing papers in "Archives of Biochemistry and Biophysics in 1981"

TL;DR: It is suggested that ascorbate plays a major role in protecting pulmonary tissue against the harmful effects of lipid peroxidation.

TL;DR: Three mechanisms for the production of OH ·, or of a comparably powerful oxidant, by metal-catalyzed interaction of O2− with H2O2, are proposed.

TL;DR: Comparison of O2 consumption at the mitochondrial, muscle, and whole-animal levels revealed that maximal muscle oxidase activity was not an absolute limitation to VO2max, and it was concluded that other factors intervene to control the percentage of muscle O 2 consumption capacity which may be utilized during exercise.

TL;DR: It is suggested that water molecules have to crystallize on the charged phospholipid interface during the rapid freezing in order to allow the fusion process to take place and to give a few examples of ionophore-mediated ion transport reactions which give rise to accumulation of protons and Ca ions inside the lipsomes.

TL;DR: The results support the conclusion that in hepatocytes catalase has a relatively minor role in catabolism of H2O2 at low rates of H 2O2 generation in the endoplasmic reticulum, but that theCatalase function increases as the rate of H1O2 production is enhanced.

TL;DR: A three-stage method is presented for the large-scale purification of calf brain tubulin, exploiting the ability of high concentrations of glutamate to stabilize tubulin and, in the presence of GTP, to induce its polymerization.

TL;DR: Catalase and Mn-superoxide dismutase protect CuZn superoxide dismutsase from inactivation and hydroxyl radical (OH.) scavengers, such as formate and mannitol, have no protective action, while results indicate that “free OH.” is not responsible for the inactivation.

TL;DR: The interaction between proteins and urea was investigated by determining the apparent partial specific volumes of nine proteins in the molecular weight range 9000 to 41,000 in 8 m urea solution and comparison with values reported in the literature for various denaturants showed good agreement.

TL;DR: In this paper, the authors showed that α S1 -casein and β-casein have a low proportion of periodic structure, but more than in the denaturing solvents, 4.5 m guanidine-hydrochloride or 6 m urea.

TL;DR: The antioxidative effect of α-tocopherol incorporated into lecithin liposomes was studied in this paper, where the peroxidation reaction was catalyzed by ascorbic acid and Fe 2+ and did not involve singlet oxygen, superoxide, hydrogen peroxide, or a hydroxyl radical.

TL;DR: It was demonstrated that NADH, molecular oxygen, linoleoyl-CoA, lipid or detergent, and three enzymes, NADH-cytochrome b 5 reductase, and the terminal enzyme, were absolutely essential for Δ 6 -desaturase, which was found to be a non-heme iron protein containing one atom of iron per one molecule of the enzyme.

TL;DR: The compositional range at which the intermediate state exists coincides with the range of maximal mitochondrial ATPase activity when these lipids are used in reconstitution experiments.

TL;DR: Purification of human leukocyte interferon by high-performance liquid chromatography yielded eight major interferons species characterized by their molecular weight, amino acid composition, and antiviral activity on human and bovine cells.

TL;DR: Iron chelated by EDTA appears to be a heretofore unrecognized requirement for the xanthine oxidase bactericidal system, and possible reasons for the relative catalytic specificity of iron-EDTA are considered.

TL;DR: It is established that anoxia induces in cultured rat hepatocytes a similar disturbance to phospholipid metabolism as does ischemia of the same cells in the intact animal, implying that the deprivation of oxygen per se determines the characteristic reaction of cells to ischemIA.

TL;DR: Methanobacterium bryantii contains a single electrophoretically discernible superoxide dismutase, which constitutes 0.4% of the extractable protein and appears to be a tetramer, which was ininhibited by N3−, but was less sensitive towards this inhibitor than other iron-containing superoxide Dismutases.

TL;DR: Results suggested that serum thiobarbituric acid values, considered to be an indicator of lipid peroxide levels, were to a significant extent due to PG endoperoxides and their derivatives.

TL;DR: It can be concluded that hydrophobic interaction is important for binding and that the combining size of the lectin is at least as large as a disaccharide, and of the compounds studied is most complementary to a mucintype disaccharacteride on a human erythrocyte membrane.

TL;DR: Enzymatic one-electron reduction of these antitumor quinones by NADPH-cytochrome P-450 reductase increased at more positive values of quinone E71, indicating that semiquinone free radicals must be generated close to the site at which they produce a biological effect.

TL;DR: The mitochondrial isozyme, SOD-3, is unlike the cytosolic isozymes in every parameter studied and appears to be similar to the mitochondrial manganese-containing Superoxide dismutases purified from other eukaryotic organisms.

TL;DR: Variation in pyrene fluorescence fine structure was investigated in alkane and alkanol solvents and solvent mixtures and yielded a curvilinear relationship as a function of dielectric constant that can be applied to monitor changes in polarity of pyrene microenvironments in proteins and membranes.

TL;DR: It is demonstrated how superoxide dismutase can inhibit cytochrome c reduction by species other than superoxide, and the implication from these findings that superoxide Dismutase-inhibitable reduction of cy tochrome c may not be a specific test for superoxide production is discussed.

TL;DR: A purification procedure for rat liver fatty acid synthetase has been developed using polyethylene glycol, which results in high yields of the enzyme which is essentially free of endogenous proteolytic nicking and also free of any contaminating proteases.

TL;DR: HT-29, a cell line derived from a human colon carcinoma, exhibits very low alkaline phosphatase activity, and is of the intestinal type, while 5-Bromo-2′-deoxyuridine and inhibitors of DNA synthesis cause a slight increase in specific activity.

TL;DR: A group of aryl sulfotransferases has been identified that catalyzes sulfate ester formation with simple phenols at an acidic pH and with several physiological metabolites at a more alkaline pH.

TL;DR: It is concluded that the individual members of the family of human leukocyte interferon proteins differ in structure and that these structural differences manifest themselves as variations in their intrinsic biological activities.

TL;DR: It appears that the rate of sucrose synthesis is largely dependent upon the supply of triose phosphate and ATP from the chloroplast and the inhibition patterns of this enzyme suggest that the enzyme operates either by an ordered bi-bi or a Theorell-Chance mechanism.

TL;DR: The endogenous levels of the various folate compounds in rat liver were determined using high-pressure liquid chromatography for the rapid separation of folate monoglutamate forms with specific quantitation of the folates by microbiological analysis of eluted fractions.