That the adenyl lipoate (AMP-lipoate) is the product of activation of lipoate was demonstrated by using the apopyruvate dehydrogenase system of Streptococcus jaecalis as well as Escherichiacoli. Pyruvate dismutation assay was used to demonstrate the activation of apoenzyme with either a mixture of ATP and lipoate or adenyl lipoate alone. That an active intermediate was formed was demonstrated b...

The two major isoforms of lipoxygenase (LOX-2 and LOX-3) from pea (Pisum sativum L. cv. Birte) seeds have been cloned and expressed from full-length cDNAs as soluble, active, non-fusion proteins in Escherichia coli. A comparison of both isoforms purified to apparent homogeneity from E. coli and pea seeds has confirmed the authenticity of the recombinant products and established the properties o...

Terminal transferase (TdT), when incubated with a purified(32)P-5"-end-labeled oligonucleotide of defined length in the presence of Co(2+), Mn(2+)or Mg(2+)and 2-mercaptoethanol in cacodylate or HEPES buffer, pH 7.2, exhibits the ability to remove a 3"-nucleotide from one oligonucleotide and add it to the 3"-end of another. When analyzed by urea-PAGE, this activity is observed as a disproportion...

Eleven flavoproteins from the old yellow enzyme family were found to catalyze the disproportionation ("dismutation") of conjugated enones. Incomplete conversions, which were attributed to enzyme inhibition by the co-product phenol could be circumvented via in situ co-product removal by scavenging the phenol using the polymeric adsorbent MP-carbonate. The optimized system allowed to reduce an al...

The production of H2O2 by cells in cold paraformaldehyde-fixed frozen sections of inflammatory lesions was histochemically demonstrated by incubating them with diaminobenzidine (DAB) for 2 to 6 h. Catalase (150 micrograms/ml, about 1400 U/ml) inhibited the reaction, indicating that H2O2 was required to produce the chromogenic DAB product. Granulocytes (PMNs and eosinophils) were the main types ...

Superoxide dismutase is an important antioxidant to control the free radical reactions related to superoxide generated in biological system. However, its large molecule and short lifespan in vivo limit its clinical use. Extensive studies have been carried out to find the suitable SOD-mimics to substitute it. In order to acts as SOD mimics, a compound should be non-toxic, stable, easy to reach i...

Catalases (CAT) are antioxidant metalloenzymes necessary for life in oxygen-metabolizing cells to regulate H2O2 concentration by accelerating its dismutation. Many physiopathological situations associated with oxidative stress resulting from overproduction, during which defenses overwhelmed. We have used a combinatorial approach an activity-based screening discover first peptidyl di-copper comp...

Endowing anti-fouling capabilities to water treatment membranes is a key feature for their long lifetime, but it continues be challenging task. Herein, strategy preparing composite reported comprising halloysite nanotubes (HNTs) as scaffolds support ruthenium substituted polyoxometalate (Ru4POM), with the goal of using evolved O2, resulting from Ru4POM-catalyzed H2O2 dismutation, agent. Two dif...

One of the major biomarkers of oxidative stress and oxidative damage of cellular DNA is 8-oxo-7,8-dihydroguanine (8-oxoGua), which is more easily oxidized than guanine to diverse oxidative products. In this work, we have investigated further oxidative transformations of 8-oxoGua in single- and double-stranded oligonucleotides to the dehydroguanidinohydantoin, oxaluric acid, and diastereomeric s...