Preceding studies (1) show that one of the products of the dismutation of cystine disulfoxide (R-(SO)z-R) is the sulfinic acid (R-SOZH), a compound which possesses greater stability in solution than any other intermediate oxidation product of cystine obtained thus far. It was interesting, therefore, to determine whether the sulfinic acid results from the dismutation of cystine in the presence o...

The dismutation of acetaldehyde to ethyl alcohol and acetic acid has been shown to occur in animal tissues (1, 2). The dependence of this reaction on diphosphopyridine nucleotide was demonstrated by von Euler and Brunius (3). Partial purification of the responsible enzyme system was achieved by Dixon and Lutwak-Mann (4). These authors clearly demonstrated that the mutase activity was independen...

Environmental stresses generate reactive oxygen species (ROS) which might be detrimental to the plants when produced in an uncontrolled way. However, the plants ameliorate such stresses by synthesizing antioxidants and enzymes responsible for the dismutation of ROS. Additionally, the dehydrins were also able to protect the inactivation of the enzyme lactate dehydrogenase against hydroxyl radica...

Nitric oxide (NO) and reactive oxygen intermediates (ROIs) play key roles in the activation of disease resistance mechanisms both in animals and plants. In animals NO cooperates with ROIs to kill tumor cells and for macrophage killing of bacteria. Such cytotoxic events occur because unregulated NO levels drive a diffusion-limited reaction with O(2)(-) to generate peroxynitrite (ONOO(-)), a medi...

The results obtained led the authors to the suggestion that Reactions 2 and 4 are catalyzed by liver alcohol dehydrogenase but that Reaction 1 is due to an aldehyde dehydrogenase present in their liver preparation. Because of the inhomogeneity of the enzyme preparation employed, a reinvestigation of this problem with more highly purified enzyme was suggested. With the use of crystalline horse l...