Antibodies directed against the autoantigen p26 were detected in sera from 32 patients with acute Epstein-Barr virus (EBV) infection and clinical symptoms of infectious mononucleosis. P26 has now been identified as the enzyme manganese superoxide dismutase (MnSOD) by comparison of the NH2-terminal amino acid sequence. Antibodies against MnSOD belong to the immunoglobulin class M. They are not d...

The fermentation of fumarate and L-malate by Clostridium formicoaceticum was investigated. Growing and nongrowing cells degraded fumarate by dismutation to succinate, acetate, and CO2; on the other hand, only small amounts of succinate were detected when the organism was grown on L-malate. This dicarboxylic acid was mainly converted to acetate and CO2. The fermentation balances were modified if...

Benzene represents the showcase of Hückel aromaticity. The silicon analog, hexasilabenzene, has consequently been targeted for decades. We now report an intensely green isomer of Si6R6 (R being 2,4,6-triisopropylphenyl) with a tricyclic structure in the solid state featuring silicon atoms with two, one, and no substituents outside the ring framework. The highly dispersed 29Si nuclear magnetic r...

Protection from oxidative damage is sufficiently important that biology has evolved three independent enzymes for hastening superoxide dismutation: the Cu- and Zn-containing superoxide dismutases (Cu,Zn-SODs), the SODs that are specific for Fe or Mn or function with either of the two (Fe-SODs, Mn-SODs or Fe/Mn-SODs), and the SODs that use Ni (Ni-SODs). Despite the overwhelming similarities betw...

An Escherichia coli double mutant, sodAsodB, that is deficient in both bacterial superoxide dismutases (Mn superoxide dismutase and iron superoxide dismutase) is unable to grow on minimal medium in the presence of oxygen and exhibits increased sensitivity to paraquat and hydrogen peroxide. Expression of the evolutionarily unrelated eukaryotic CuZn superoxide dismutase in the sodAsodB E. coli mu...

Reactive sulfur species (RSS) such as H2S, HS•, H2Sn, (n = 2-7) and HS2•- are chemically similar to H2O and the reactive oxygen species (ROS) HO•, H2O2, O2•- and act on common biological effectors. RSS were present in evolution long before ROS, and because both are metabolized by catalase it has been suggested that "antioxidant" enzymes originally evolved to regulate RSS and may continue to do ...

The induction of hydroxyl radical (OH) production via quinone redox cycling in white-rot fungi was investigated to improve pollutant degradation. In particular, we examined the influence of 4-methoxybenzaldehyde (anisaldehyde), Mn(2+), and oxalate on Pleurotus eryngii OH generation. Our standard quinone redox cycling conditions combined mycelium from laccase-producing cultures with 2,6-dimethox...

Hematoporphyrin derivative (HpD) is a systemically administered photosensitizing agent that may be of value in the treatment of solid tumors. When corneal endothelial cells were perfused in the specular microscope with HpD and exposed to a 25-W incandescent light at 5 cm (5.5 mW/cm) there was anatomic disruption of corneal endothelial cells and swelling of the corneal stroma. Perfusion with 0.2...

Reduced oxygen intermediates are produced in plant tissues from mitochondrial and chloroplastic electron transport pathways and from electron-saturated photosynthetic pigments (Bowler et al., 1992). For instance, the Mehler reaction is a primary source of reduced oxygen intermediates in chloroplasts in which dioxygen is reduced by Fd on the reducing side of PSI to produce .O2-. The dismutation ...

Superoxide dismutases (SODs) catalyze the dismutation of superoxide radicals in a broad range of organisms, including plants. Quantification of SOD activity in crude plant extracts has been problematic due to the presence of compounds that interfere with the dose-response of the assay. Although strategies exist to partially purify SODs from plant extracts, the requirement for purification limit...