Superoxide dismutase bacteria producing

Superoxide is formed (reaction 1) in the red blood cell by the auto-oxidation of hemoglobin to methemo-globin (approximately 3% of hemoglobin in human red blood cells has been calculated to auto-oxidize per day) in other tissues, it is formed by the action of enzymes such as cytochrome P450 reductase and xanthine oxidase. When stimulated by contact with bacteria, neutrophils exhibit a respiratory burst (see below) and produce superoxide in a reaction catalyzed by NADPH oxidase (reaction 2). Superoxide spontaneously dismu-tates to form H2O2 and O2 however, the rate of this same reaction is speeded up tremendously by the action of the enzyme superoxide dismutase (reaction 3). Hydrogen peroxide is subject to a number of fates. The enzyme catalase, present in many types of cells, converts... 

The bacterium Lactobacillus plantarum and its closest allies are unusual in that they are aerobic organisms but do not produce a superoxide dismutase. This bacterium instead accumulates Mn(II) to an intramolecular level on the order of 25 mM (150-152). In vitro studies indicated that Mn(II) formed a complex with lactate which possessed significant superoxide activity (153). These bacteria are additionally unable to produce heme and, consequently, when grown in the absence of heme, produce a hemeless catalase, or pseudocatalase (154-158). Unlike heme-containing catalases, the enzyme is not inhibited by cyanide or azide, and the addition of either Mn or Fe into the growth medium increased the amount of the pseudocatalase present. However, neither of the metals could be detected in partially purified enzyme assays (157). 

Most lactic acid bacteria tolerate the presence of oxygen but do not use it in energy-producing mechanisms. Depending on the species, they use different pathways to eliminate the toxic peroxide, activating peroxidases which use NADH as a reducer a superoxide dismutase, a pseudo catalase and sometimes Mn + ions (Desmazeaud and Roissart, 1994). To date, this subject has not been specifically studied for species isolated in wine. 

Han, W., Meroenier, A., Ait-Belgnaoui, A., et al. (2006) Improvement of an experimental cohtis in rats by lactic acid bacteria producing superoxide dismutase. Inflamm Bowel Dis 12,1044-1052. 

LeBlanc, J.G., del Carmen, S., Miyoshi, A., et al. (2011) Use of superoxide dismutase and catalase producing lactic acid bacteria in TNBS induced Crohn s disease in mice. J Biotechnol 151, 287-293. 

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