Showing papers in "Archives of Biochemistry and Biophysics in 1982"

TL;DR: The results support the earlier proposal that DT-diaphorase serves as a cellular control device against quinone toxicity and reflects the relative contributions of the two pathways.

TL;DR: Findings support the hypothesis that oxygen toxicity is in part a consequence of increased rates of intracellular O2− and H2O2 production.

TL;DR: In this paper, the authors examined the mechanisms by which Mn catalytically scavenges O2−, both in the xanthine oxidase/cytochrome c SOD assay and in a number of in vitro systems relevant to the in vivo situation.

TL;DR: The enhanced release of H2O2 by hyperoxic mitochondria and microsomes may be responsible, in part, for the cellular damage observed in lungs of animals breathing oxygen concentrations of 60% or greater.

TL;DR: The great flexibility of purification procedure involving silica sols was extended from mitochondria to the isolation of intact peroxisomes and Percoll-purified mitochondria showed improved rates of substrate oxidation, respiratory control, and ADP:O ratios.

TL;DR: This newly isolated hemoprotein, cytochrome P -450 e, is inducible in rat liver by Aroclor 1254 and phenobarbital, but not by 3-methylcholanthrene.

TL;DR: Incubation of normal rat lung homogenates under hyperoxic conditions also acutely increased lipid peroxidation, which confirms that hyperoxia enhances cellular production of O 2 − and H 2 O 2 and implies an essential role for both O 2− and H2 O 2 in hyperoxic lung damage.

TL;DR: A 14-residue peptide toxin has been isolated from the venom of the marine snail Conus magus, and is presumed to act as they do at the acetylcholine receptor of vertebrate neuromuscular junctions.

TL;DR: It is proposed that initiation of superoxide-dependent lipid peroxidation in the presence of EDTA-chelated iron occurs via the hydroxyl radical, as evidenced by malondialdehyde and lipid hydroperoxide formation.

TL;DR: Fe3+-EDTA chelates react with the superoxide radical at physiological pH values but do not appear to catalyze O2⨪ dismutation at a significant rate, while complexes of Fe3+ with desferrioxamine, bathophenanthroline, or diethylenetriaminepentaacetic acid react much more slowly, if at all.

TL;DR: It is concluded that the malate aspartate shuttle may be involved in stimulus secretion coupling for glucose-induced insulin release in rat pancreatic islets.

TL;DR: Four hybridomas obtained from mice immunized with human adenocarcinomas of colon or stomach produce antibodies that bind specifically in solid-phase radioimmunoassay to the ceramide pentasaccharide that contains the lacto-N-fucopentaose III sequence of sugars.

TL;DR: Two inhibitors of thrombin-stimulated arachidonic acid release from platelets, p-bromophenacyl bromide and mepacrine, were examined for their ability to inhibit the phosphatidylinositol-specific phospholipase C-diglyceride lipase pathway.

TL;DR: The molecular weight of native potato inhibitor I was reevaluated by rigorous ultracentrifugal analysis and compared with data from previous analyses and confirms that native inhibitor I has a native M r of about 41,000 and is a pentamer.

TL;DR: It is determined that the superoxide-dependent oxidation of one particular hydroxylamine, 2-ethyl-1-hydroxy-2,5,5-trimethyl-3-oxazolidine, to its corresponding nitroxide, can be used to quantitate superoxide production by hepatic microsomes and purified enzymes.

TL;DR: The forward mitochondrial creatine kinase reaction appears to be altered from its normal rapid-equilibrium random binding kinetics to some other mechanism by its coupling to oxidative phosphorylation.

TL;DR: The systematic screening of over 150 compounds for inhibitory activity on mammalian cytosolic epoxide hydrolase led to identification of chalcone oxide (trans-1-benzoyl-2-phenyloxirane) as an optimal inhibitory structure, indicating different catalytic mechanisms.

TL;DR: These experiments establish the existence of a selenoprotein, 75 Se-P, in rat liver and plasma which is chromatographically distinct from glutathione peroxidase and which incorporates 75 Se differently from glutATHione per oxidase.

TL;DR: Spermine was found to bind more to a GC-rich DNA and the binding of spermine to RNA was greater than that to DNA in the presence of more than 2 m m Mg2+ and 100 m m K+ concentration.

TL;DR: A low-molecular-weight human liver acid phosphatase was purified 2580-fold to homogenity by a procedure involving ammonium sulfate fractionation, acid treatment, and SP-Sephadex ion-exchange chromatography with ion-affinity elution.

TL;DR: Experiments were performed which illustrate the various ways EDTA can influence lipid peroxidation and the addition of EDTA, rather than EDTA-Fe 3+ inhibited the liposomalPeroxidation catalyzed by either enzyme with ADP-Fe3+ when the EDTA concentration exceeded the concentration of Fe 3+.

TL;DR: Although normally BLC has only 506 residues, there is evidence that, at some point in its history, it also had the C-terminal extension, and it is speculated that this extension is lost in BLC either through a different processing of the molecule in liver than in erythrocytes or by partial degradation in the first stages of catabolism.

TL;DR: Reversible LHC-II phosphorylation provides the physiological mechanism for the control of the distribution of absorbed excitation energy between the two photosystems.

TL;DR: It is demonstrated that hydroxyproline in the X-position of the repeating -glycine-X-Y- sequences decreases rather than increases, the thermal stability of the triple helix.

TL;DR: It is shown that the reversible transitions between anaerobic dormancy and aerobic development are accompanied by large intracellular pH changes, the more acid pH being associated with the dormant state, suggesting the potential for pH-mediated regulation of enzyme activities during dormancy.

TL;DR: Benznidazole (a nitroimidazoles derivative used for the treatment of Chagas' disease) is reduced by rat liver microsomes to the nitro anion radical, as indicated by ESR spectroscopy.

TL;DR: The electron spin resonance of Mn(II)-polyphosphate, in the presence of orthophosphate and NaCl, approximated that of cell extracts in this paper.

TL;DR: It appears likely that the diverse biological effects of peroxidases are largely due to the reactivities of these intermediates and products.

TL;DR: Hepatic soluble guanylate cyclase appears to possess SH groups required for catalysis and to require heme and/or other unknown factors for the full expression of enzyme activation by NO and nitroso compounds.

TL;DR: The A conformer (metal ion-free form) of α-lactalbumin binds ANS and TNS more tightly than the N (native) form of the protein with marked fluorescence enhancement as mentioned in this paper.