The trypanosomatid flavoprotein disulfide reductase, trypanothione reductase, is shown to catalyze one-electron reduction of suitably substituted naphthoquinone and nitrofuran derivatives. A number of such compounds have been chemically synthesized, and a structure-activity relationship has been established; the enzyme is most active with compounds that contain basic functional groups in side-c...

Introduction: Triphala, consisting of three fruits, Phyllanthus emblica L. (Phyllanthaceae), Terminalia bellirica (Gaertn.) Roxb. (Combretaceae), and T. chebula Retz, is a well-recognized Ayurvedic herbal formulation, used for various therapeutic purposes, including the treatment dyslipidemia. Inhibitory activity against 3‑hydroxy‑3‑methylglutaryl‑coenzyme A (HMG‑CoA) reductase, rate-limiting e...

3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMG CoA reductase) controls the rate of cholesterol biosynthesis and is itself modulated through feedback suppression by internalized low density lipoprotein (LDL) cholesterol. We measured HMG CoA reductase protein concentration and microsomal enzyme activity in freshly isolated mononuclear leukocytes from normal individuals and patients with het...

Molybdenum is absolutely required for the nitrate-reducing activity of the nicotinamide adenine dinucleotide nitrate reductase complex isolated from Chlorella fusca. The whole enzyme nicotinamide adenine dinucleotide nitrate reductase is formed by cells grown in the absence of added molybdate, but only its first activity (nicotinamide adenine dinucleotide diaphorase) is functional. The second a...

The liver, kidney and spleen of the mouse and rat and the kidney and spleen of the ox express a monomeric form of biliverdin reductase (Mr 34,000), which in the case of the ox kidney enzyme exists in two forms (pI 5.4 and 5.2) that are probably charge isomers. The livers of the mouse and rats express, in addition, a protein (Mr 46,000) that cross-reacts with antibodies raised against the ox kid...

The biosynthesis of long chain aliphatic aldehydes for light emission in luminescent bacteria is catalyzed by a fatty acid reductase in a reaction dependent on ATP and NADPH. Evidence has now been obtained which demonstrates that this reaction consists of two distinct steps: 1) activation of fatty acid and 2) reduction of a fatty acyl intermediate to aldehyde. Fatty acid reductase catalyzed the...

d-Lactate accumulation in Chlamydomonas reinhardtii was dependent on anaerobic conditions. As much as 50% of the (14)C after 2 minutes of photosynthetic (14)CO(2) fixation moved into d-lactate from sugar phosphates if the cells became anaerobic for short time periods. No lactate accumulated in the dark until the O(2) concentration decreased to less than 0.1%. Lactate was determined to be of the...

Flavin-Containing Enzyme, Nitrate Reductase, Ankistrodesmus braunii Ankistrodesmus braunii NAD(P)H-nitrate reductase is a complex hemoflavomolybdoprotein composed by eight similar subunits. The flavin prosthetic group, identified as FAD, is essential for the NAD(P)H-dependent activities of the complex, and is located before the heme chromophore in the enzyme electron transport chain from reduce...

Quercetin and galangin can change the activity of glutathione reductase. Quercetin (a catechol structure in the B-ring) and galangin (any hydroxyl group in the B-ring) have different biological activities but, both possess high antioxidant abilities. Quercetin during the antioxidative action, is converted into an oxidized products (o-semiquinone and o-quinone), and subsequently glutathionyl add...

In forest ecosystems, variations in aboveground litter input caused by global changes, substantially alter soil N cycling. field-grown plants, few studies have directly measured root exudation rates and quantified their effects on transformations under manipulation. We transformation rate responses to manipulation a Pinus massoniana plantation, unravelled the effect of transformations. situ P. ...