Oxidative cyclizations, exemplified by the biosynthetic assembly of the penicillin nucleus from a tripeptide precursor, are arguably the most synthetically powerful implementation of C-H activation reactions in nature. Here, we show that Rieske oxygenase-like enzymes mediate regio- and stereodivergent oxidative cyclizations to form 10- and 12-membered carbocyclic rings in the key steps of the b...

The enzymatic conversion of plant biomass has been recently revolutionized by the discovery of lytic polysaccharide monooxygenases (LPMOs) that carry out oxidative cleavage of polysaccharides. These very powerful enzymes are abundant in fungal saprotrophs. LPMOs require activation by electrons that can be provided by cellobiose dehydrogenases (CDHs), but as some fungi lack CDH-encoding genes, o...

Increased mesangial cell proliferation is a hallmark of many glomerulopathies in humans. Whereas the pathogenic role of reactive oxygen species (ROS) in the development of experimental mesangioproliferative glomerulonephritis (GN) is well established, very little is known about the mechanisms leading to increased ROS concentrations in the glomerulus. This study therefore examined glomerular ROS...

BACKGROUND & OBJECTIVES Oxidative stress is incriminated to play a central role in the pathogenesis of Parkinson's disease (PD). Oxidative stress, to which neurons are highly susceptible, is also known to induce oxidative changes in human red blood cells (RBCs), in vivo and in vitro. Earlier studies on oxidative stress in RBCs in patients with PD have yielded controversial results claiming unal...

It has become increasingly evident that chronic inflammation underpins the development of many chronic diseases including cancer, cardiovascular disease and type 2 diabetes. Oxidative stress is inherently a biochemical dysregulation of the redox status of the intracellular environment, which under homeostatic conditions is a reducing environment, whereas inflammation is the biological response ...

The present study aimed to describe the expression and purification of cyclophilin-type peptidylprolyl cis-trans isomerase (PPI) from the red alga Pyropia yezoensis. The antioxidant activity of the purified protein was also demonstrated, based on its ability to act against oxidative stress in HepG2 human hepatocellular carcinoma cells. HepG2 cells that were treated with recombinant PPI protein ...

Recently, the salivary glands function from biochemical, physiological and histochemical standpoints have been rather highlighted. Many investigators have come to try a histochemical detection of enzymes participating in various metabolic pathway in the salivary glands of experimental animals and humans. The previous study of this series dealt with the histochemical demonstration of various hyd...

The aim of this work was to study drought effects on lipid peroxidation, antioxidant compounds, and anti-oxidative enzymes activities in two tolerant (Daric and 92 Zhong), two moderately tolerant (Sabalan and DH-2049-3) and two sensitive (Shark and Tevees) wheat genotypes. Malondialdehyde content and electrolyte leakage increased significantly (P