Modified electrodes using immobilized alcohol dehydrogenase enzymes for the efficient electroreduction of butyraldehyde to butanol are presented as an important step for the utilization of CO2-reduction products. Alcohol dehydrogenase was immobilized, embedded in an alginate-silicate hybrid gel, on a carbon felt (CF) electrode. The application of this enzyme to the reduction of an aldehyde to a...

Mitochondria are exposed to reactive nitrogen species under physiological conditions and even more under several pathologic states. In order to reveal the mechanism of these processes we studied the effects of peroxynitrite on isolated beef heart mitochondria in vitro. Peroxynitrite has the potential to nitrate protein tyrosine moieties, break the peptide bond, and eventually release the membra...

The chain oxidation of glyceraldehyde-3-phosphate dehydrogenase.NADH by perhydroxyl radicals and propagated by molecular oxygen was studied by the xanthine-xanthine oxidase system, 60Co gamma-ray, and pulse radiolysis. The chain length, amount of NADH oxidized per HO2 generated, increases with increasing acidity of the medium and reaches a value of 73 at pH 5.0. The rate constant for the oxidat...

Mycobacterium tuberculosis can maintain a nonreplicating persistent state in the host for decades, but must maintain the ability to efficiently reactivate and produce active disease to survive and spread in a population. Among the enzymes expressed during this dormancy is alanine dehydrogenase, which converts pyruvate to alanine, and glyoxylate to glycine concurrent with the oxidation of NADH t...

Oxidative stress is associated with the formation of oxidized glutathione (GSSG) in the cells, which can form mixed disulfide with proteins leading to alteration of their function. The present study looks at the effect of in vitro exposure of GSSG on intestinal mitochondria and brush border membrane (BBM). Incubation with 1 mM GSSG increased the protein bound GSH in mitochondria by 15-fold. Thi...

A new species of Ptyctolaemus Peters, 1864 is described from Htamanthi Wildlife Sanctuary, Sagaing Division, Myanmar. The differs P. gularis and aff. Tibet, China, by having relatively longer limbs different colorations the gular region, it collicristatus much a less developed nuchal crest in males. Moreover, genetically an uncorrected percentage distance 23.5% 24.8%, respectively, inferred mit...

The complete solution to the kinetic equation for nucleotide fluorescence quenching on addition of pyruvate to the late dehydrogenase-NADH complex modifies previous interpretations of such experiments.

Intact human erythrocytes were exposed to low concentrations of glutaraldehyde. After washing and subsequent lysis of the cells, glyceraldehyde 3-phosphate dehydrogenase activity is found to be associated with a membrane fraction and cannot be eluted by salt treatment. Lactate dehydrogenase activity is associated with a supernatant fraction under the same conditions. Preincubation of the intact...