Many gram-negative bacteria harbor a copper/zinc-containing superoxide dismutase (CuZnSOD) in their periplasms. In pathogenic bacteria, one role of this enzyme may be to protect periplasmic biomolecules from superoxide that is released by host phagocytic cells. However, the enzyme is also present in many nonpathogens and/or free-living bacteria, including Escherichia coli. In this study we were...

Cytochrome c was reduced when superoxide was generated from xanthine oxidase in the presence of alloxan, and by the reaction of alloxan and with reduced glutathione. In each case, most of the reduction was inhibited by superoxide dismutase, but considerably more enzyme was required than with superoxide alone. This indicates that the superoxide dismutase-inhibitible cytochrome c reduction was ma...

background: the possibility of impaired antioxidant status and so increased oxidative damage in periodontal disease is being conjectured. the present randomized controlled study was carried out with the objective of analyzing the activity of superoxide dismutase enzyme and thiol antioxidants in gingival crevicular fluid (gcf) and saliva as indicators of response to periodontal therapy. material...