Plasma Enzyme Activities in Coturnix Quail Fed Graded Doses of DDE, Polychlorinated Biphenyl, Malathion and Mercuric Chloride. DIETER, M. P. (1974). Toxicol. Appl. Pharmacol. 27, 86-98. Male Coturnix quail (Coturnix coturnixjaponica) were fed diets for 12 weeks containing graded levels of DDE, polychlorinated biphenyl (Aroclor 1254), malathion, and mercuric chloride. Birds were bled prior to ex...

Archaeoglobus fulgidus, a hyperthermophilic sulfate-reducing Archaeon, contains high Fe(3+)-EDTA reductase activity in its soluble protein fraction. The corresponding enzyme, which constitutes about 0.75% of the soluble protein, was purified 175-fold to homogeneity. Based on SDS-polyacrylamide gel electrophoresis, the ferric reductase consists of a single subunit with a M(r) of 18,000. The M(r)...

A monomeric (Mr = 43,000) NADPH-dependent oxidoreductase with a broad substrate specificity for aliphatic and aromatic aldehydes and aldo sugars has been purified from the skeletal muscle of female and castrated pigs. The properties of this enzyme are consistent with those of aldose reductase (EC 1.1.1.21), and the enzyme is immunologically identical with aldose reductase from pig lens. However...

A barley (Hordeum vulgare L.) mutant, nar1a (formerly Az12), deficient in NADH nitrate reductase activity is, nevertheless, capable of growth with nitrate as the sole nitrogen source. In an attempt to identify the mechanism(s) of nitrate reduction in the mutant, nitrate reductase from nar1a was characterized to determine whether the residual activity is due to a leaky mutation or to the presenc...

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase from rat liver microsomes has been purified to apparent homogeneity with recoveries of approximately 50%. The enzyme obtained from rats fed a diet supplemented with cholestyramine had specific activities of approximately 21,500 nmol of NADPH oxidized/min/mg of protein. After amino acid analysis a specific activity of 31,000 nmol of NADPH...

The initial-rate kinetics of the flavin reductase reaction catalysed by biliverdin-IXbeta reductase at pH 7.5 are consistent with a rapid-equilibrium ordered mechanism, with the pyridine nucleotide binding first. NADPH binding to the free enzyme was characterized using stopped-flow fluorescence quenching, and a K(d) of 15.8 microM was calculated. Equilibrium fluorescence quenching experiments i...

The methotrexate-resistant AT-3000 line of S-180 cells has at least 150-fold more immunologically cross-reactive folate reductase than sensitive cells. Highly specific immunologic and protein purification procedures were used to show that the increased enzyme levels in this line are due to a corresponding increase in the rate of folate reductase synthesis. This observation indicates that the re...

abstract mercury compounds are widely used in several industries. such compounds can find their way to the environment causing its pollution. mercury is considered as a powerful carcinogenic agent. on the other side, the garlic extract is characterized by having compounds of specific anticarcinogenic action. therefore, the present study was conducted to investigate both the genotoxicity and cyt...